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1485 lines
36 KiB
1485 lines
36 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* ADS7846 based touchscreen and sensor driver |
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* |
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* Copyright (c) 2005 David Brownell |
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* Copyright (c) 2006 Nokia Corporation |
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* Various changes: Imre Deak <[email protected]> |
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* |
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* Using code from: |
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* - corgi_ts.c |
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* Copyright (C) 2004-2005 Richard Purdie |
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* - omap_ts.[hc], ads7846.h, ts_osk.c |
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* Copyright (C) 2002 MontaVista Software |
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* Copyright (C) 2004 Texas Instruments |
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* Copyright (C) 2005 Dirk Behme |
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*/ |
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#include <linux/types.h> |
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#include <linux/hwmon.h> |
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#include <linux/err.h> |
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#include <linux/sched.h> |
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#include <linux/delay.h> |
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#include <linux/input.h> |
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#include <linux/input/touchscreen.h> |
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#include <linux/interrupt.h> |
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#include <linux/slab.h> |
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#include <linux/pm.h> |
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#include <linux/of.h> |
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#include <linux/of_gpio.h> |
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#include <linux/of_device.h> |
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#include <linux/gpio.h> |
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#include <linux/spi/spi.h> |
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#include <linux/spi/ads7846.h> |
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#include <linux/regulator/consumer.h> |
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#include <linux/module.h> |
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#include <asm/unaligned.h> |
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|
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/* |
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* This code has been heavily tested on a Nokia 770, and lightly |
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* tested on other ads7846 devices (OSK/Mistral, Lubbock, Spitz). |
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* TSC2046 is just newer ads7846 silicon. |
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* Support for ads7843 tested on Atmel at91sam926x-EK. |
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* Support for ads7845 has only been stubbed in. |
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* Support for Analog Devices AD7873 and AD7843 tested. |
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* |
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* IRQ handling needs a workaround because of a shortcoming in handling |
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* edge triggered IRQs on some platforms like the OMAP1/2. These |
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* platforms don't handle the ARM lazy IRQ disabling properly, thus we |
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* have to maintain our own SW IRQ disabled status. This should be |
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* removed as soon as the affected platform's IRQ handling is fixed. |
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* |
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* App note sbaa036 talks in more detail about accurate sampling... |
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* that ought to help in situations like LCDs inducing noise (which |
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* can also be helped by using synch signals) and more generally. |
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* This driver tries to utilize the measures described in the app |
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* note. The strength of filtering can be set in the board-* specific |
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* files. |
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*/ |
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|
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#define TS_POLL_DELAY 1 /* ms delay before the first sample */ |
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#define TS_POLL_PERIOD 5 /* ms delay between samples */ |
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|
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/* this driver doesn't aim at the peak continuous sample rate */ |
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#define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */) |
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|
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struct ads7846_buf { |
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u8 cmd; |
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__be16 data; |
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} __packed; |
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|
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struct ads7846_buf_layout { |
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unsigned int offset; |
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unsigned int count; |
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unsigned int skip; |
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}; |
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|
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/* |
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* We allocate this separately to avoid cache line sharing issues when |
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* driver is used with DMA-based SPI controllers (like atmel_spi) on |
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* systems where main memory is not DMA-coherent (most non-x86 boards). |
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*/ |
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struct ads7846_packet { |
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unsigned int count; |
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unsigned int count_skip; |
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unsigned int cmds; |
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unsigned int last_cmd_idx; |
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struct ads7846_buf_layout l[5]; |
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struct ads7846_buf *rx; |
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struct ads7846_buf *tx; |
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struct ads7846_buf pwrdown_cmd; |
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bool ignore; |
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u16 x, y, z1, z2; |
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}; |
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struct ads7846 { |
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struct input_dev *input; |
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char phys[32]; |
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char name[32]; |
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struct spi_device *spi; |
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struct regulator *reg; |
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#if IS_ENABLED(CONFIG_HWMON) |
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struct device *hwmon; |
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#endif |
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u16 model; |
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u16 vref_mv; |
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u16 vref_delay_usecs; |
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u16 x_plate_ohms; |
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u16 pressure_max; |
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bool swap_xy; |
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bool use_internal; |
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struct ads7846_packet *packet; |
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struct spi_transfer xfer[18]; |
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struct spi_message msg[5]; |
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int msg_count; |
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wait_queue_head_t wait; |
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bool pendown; |
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int read_cnt; |
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int read_rep; |
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int last_read; |
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u16 debounce_max; |
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u16 debounce_tol; |
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u16 debounce_rep; |
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u16 penirq_recheck_delay_usecs; |
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struct touchscreen_properties core_prop; |
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struct mutex lock; |
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bool stopped; /* P: lock */ |
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bool disabled; /* P: lock */ |
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bool suspended; /* P: lock */ |
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int (*filter)(void *data, int data_idx, int *val); |
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void *filter_data; |
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void (*filter_cleanup)(void *data); |
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int (*get_pendown_state)(void); |
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int gpio_pendown; |
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|
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void (*wait_for_sync)(void); |
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}; |
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/* leave chip selected when we're done, for quicker re-select? */ |
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#if 0 |
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#define CS_CHANGE(xfer) ((xfer).cs_change = 1) |
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#else |
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#define CS_CHANGE(xfer) ((xfer).cs_change = 0) |
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#endif |
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/*--------------------------------------------------------------------------*/ |
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|
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/* The ADS7846 has touchscreen and other sensors. |
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* Earlier ads784x chips are somewhat compatible. |
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*/ |
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#define ADS_START (1 << 7) |
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#define ADS_A2A1A0_d_y (1 << 4) /* differential */ |
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#define ADS_A2A1A0_d_z1 (3 << 4) /* differential */ |
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#define ADS_A2A1A0_d_z2 (4 << 4) /* differential */ |
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#define ADS_A2A1A0_d_x (5 << 4) /* differential */ |
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#define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */ |
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#define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */ |
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#define ADS_A2A1A0_vaux (6 << 4) /* non-differential */ |
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#define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */ |
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#define ADS_8_BIT (1 << 3) |
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#define ADS_12_BIT (0 << 3) |
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#define ADS_SER (1 << 2) /* non-differential */ |
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#define ADS_DFR (0 << 2) /* differential */ |
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#define ADS_PD10_PDOWN (0 << 0) /* low power mode + penirq */ |
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#define ADS_PD10_ADC_ON (1 << 0) /* ADC on */ |
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#define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */ |
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#define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */ |
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#define MAX_12BIT ((1<<12)-1) |
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/* leave ADC powered up (disables penirq) between differential samples */ |
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#define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \ |
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| ADS_12_BIT | ADS_DFR | \ |
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(adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0)) |
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#define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref)) |
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#define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref)) |
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#define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref)) |
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#define READ_X(vref) (READ_12BIT_DFR(x, 1, vref)) |
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#define PWRDOWN (READ_12BIT_DFR(y, 0, 0)) /* LAST */ |
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/* single-ended samples need to first power up reference voltage; |
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* we leave both ADC and VREF powered |
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*/ |
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#define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \ |
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| ADS_12_BIT | ADS_SER) |
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#define REF_ON (READ_12BIT_DFR(x, 1, 1)) |
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#define REF_OFF (READ_12BIT_DFR(y, 0, 0)) |
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/* Order commands in the most optimal way to reduce Vref switching and |
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* settling time: |
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* Measure: X; Vref: X+, X-; IN: Y+ |
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* Measure: Y; Vref: Y+, Y-; IN: X+ |
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* Measure: Z1; Vref: Y+, X-; IN: X+ |
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* Measure: Z2; Vref: Y+, X-; IN: Y- |
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*/ |
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enum ads7846_cmds { |
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ADS7846_X, |
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ADS7846_Y, |
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ADS7846_Z1, |
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ADS7846_Z2, |
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ADS7846_PWDOWN, |
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}; |
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static int get_pendown_state(struct ads7846 *ts) |
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{ |
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if (ts->get_pendown_state) |
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return ts->get_pendown_state(); |
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return !gpio_get_value(ts->gpio_pendown); |
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} |
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static void ads7846_report_pen_up(struct ads7846 *ts) |
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{ |
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struct input_dev *input = ts->input; |
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|
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input_report_key(input, BTN_TOUCH, 0); |
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input_report_abs(input, ABS_PRESSURE, 0); |
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input_sync(input); |
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ts->pendown = false; |
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dev_vdbg(&ts->spi->dev, "UP\n"); |
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} |
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/* Must be called with ts->lock held */ |
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static void ads7846_stop(struct ads7846 *ts) |
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{ |
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if (!ts->disabled && !ts->suspended) { |
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/* Signal IRQ thread to stop polling and disable the handler. */ |
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ts->stopped = true; |
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mb(); |
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wake_up(&ts->wait); |
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disable_irq(ts->spi->irq); |
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} |
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} |
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/* Must be called with ts->lock held */ |
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static void ads7846_restart(struct ads7846 *ts) |
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{ |
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if (!ts->disabled && !ts->suspended) { |
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/* Check if pen was released since last stop */ |
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if (ts->pendown && !get_pendown_state(ts)) |
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ads7846_report_pen_up(ts); |
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|
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/* Tell IRQ thread that it may poll the device. */ |
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ts->stopped = false; |
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mb(); |
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enable_irq(ts->spi->irq); |
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} |
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} |
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/* Must be called with ts->lock held */ |
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static void __ads7846_disable(struct ads7846 *ts) |
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{ |
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ads7846_stop(ts); |
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regulator_disable(ts->reg); |
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/* |
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* We know the chip's in low power mode since we always |
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* leave it that way after every request |
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*/ |
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} |
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/* Must be called with ts->lock held */ |
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static void __ads7846_enable(struct ads7846 *ts) |
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{ |
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int error; |
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error = regulator_enable(ts->reg); |
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if (error != 0) |
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dev_err(&ts->spi->dev, "Failed to enable supply: %d\n", error); |
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ads7846_restart(ts); |
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} |
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static void ads7846_disable(struct ads7846 *ts) |
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{ |
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mutex_lock(&ts->lock); |
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if (!ts->disabled) { |
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if (!ts->suspended) |
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__ads7846_disable(ts); |
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ts->disabled = true; |
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} |
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mutex_unlock(&ts->lock); |
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} |
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static void ads7846_enable(struct ads7846 *ts) |
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{ |
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mutex_lock(&ts->lock); |
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if (ts->disabled) { |
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ts->disabled = false; |
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if (!ts->suspended) |
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__ads7846_enable(ts); |
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} |
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mutex_unlock(&ts->lock); |
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} |
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/*--------------------------------------------------------------------------*/ |
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/* |
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* Non-touchscreen sensors only use single-ended conversions. |
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* The range is GND..vREF. The ads7843 and ads7835 must use external vREF; |
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* ads7846 lets that pin be unconnected, to use internal vREF. |
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*/ |
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struct ser_req { |
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u8 ref_on; |
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u8 command; |
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u8 ref_off; |
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u16 scratch; |
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struct spi_message msg; |
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struct spi_transfer xfer[6]; |
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/* |
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* DMA (thus cache coherency maintenance) requires the |
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* transfer buffers to live in their own cache lines. |
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*/ |
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__be16 sample ____cacheline_aligned; |
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}; |
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struct ads7845_ser_req { |
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u8 command[3]; |
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struct spi_message msg; |
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struct spi_transfer xfer[2]; |
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/* |
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* DMA (thus cache coherency maintenance) requires the |
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* transfer buffers to live in their own cache lines. |
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*/ |
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u8 sample[3] ____cacheline_aligned; |
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}; |
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static int ads7846_read12_ser(struct device *dev, unsigned command) |
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{ |
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struct spi_device *spi = to_spi_device(dev); |
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struct ads7846 *ts = dev_get_drvdata(dev); |
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struct ser_req *req; |
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int status; |
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req = kzalloc(sizeof *req, GFP_KERNEL); |
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if (!req) |
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return -ENOMEM; |
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spi_message_init(&req->msg); |
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/* maybe turn on internal vREF, and let it settle */ |
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if (ts->use_internal) { |
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req->ref_on = REF_ON; |
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req->xfer[0].tx_buf = &req->ref_on; |
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req->xfer[0].len = 1; |
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spi_message_add_tail(&req->xfer[0], &req->msg); |
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req->xfer[1].rx_buf = &req->scratch; |
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req->xfer[1].len = 2; |
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/* for 1uF, settle for 800 usec; no cap, 100 usec. */ |
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req->xfer[1].delay.value = ts->vref_delay_usecs; |
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req->xfer[1].delay.unit = SPI_DELAY_UNIT_USECS; |
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spi_message_add_tail(&req->xfer[1], &req->msg); |
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/* Enable reference voltage */ |
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command |= ADS_PD10_REF_ON; |
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} |
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/* Enable ADC in every case */ |
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command |= ADS_PD10_ADC_ON; |
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/* take sample */ |
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req->command = (u8) command; |
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req->xfer[2].tx_buf = &req->command; |
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req->xfer[2].len = 1; |
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spi_message_add_tail(&req->xfer[2], &req->msg); |
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req->xfer[3].rx_buf = &req->sample; |
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req->xfer[3].len = 2; |
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spi_message_add_tail(&req->xfer[3], &req->msg); |
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/* REVISIT: take a few more samples, and compare ... */ |
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/* converter in low power mode & enable PENIRQ */ |
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req->ref_off = PWRDOWN; |
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req->xfer[4].tx_buf = &req->ref_off; |
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req->xfer[4].len = 1; |
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spi_message_add_tail(&req->xfer[4], &req->msg); |
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req->xfer[5].rx_buf = &req->scratch; |
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req->xfer[5].len = 2; |
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CS_CHANGE(req->xfer[5]); |
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spi_message_add_tail(&req->xfer[5], &req->msg); |
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mutex_lock(&ts->lock); |
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ads7846_stop(ts); |
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status = spi_sync(spi, &req->msg); |
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ads7846_restart(ts); |
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mutex_unlock(&ts->lock); |
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if (status == 0) { |
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/* on-wire is a must-ignore bit, a BE12 value, then padding */ |
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status = be16_to_cpu(req->sample); |
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status = status >> 3; |
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status &= 0x0fff; |
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} |
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kfree(req); |
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return status; |
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} |
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static int ads7845_read12_ser(struct device *dev, unsigned command) |
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{ |
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struct spi_device *spi = to_spi_device(dev); |
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struct ads7846 *ts = dev_get_drvdata(dev); |
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struct ads7845_ser_req *req; |
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int status; |
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req = kzalloc(sizeof *req, GFP_KERNEL); |
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if (!req) |
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return -ENOMEM; |
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spi_message_init(&req->msg); |
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req->command[0] = (u8) command; |
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req->xfer[0].tx_buf = req->command; |
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req->xfer[0].rx_buf = req->sample; |
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req->xfer[0].len = 3; |
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spi_message_add_tail(&req->xfer[0], &req->msg); |
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mutex_lock(&ts->lock); |
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ads7846_stop(ts); |
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status = spi_sync(spi, &req->msg); |
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ads7846_restart(ts); |
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mutex_unlock(&ts->lock); |
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if (status == 0) { |
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/* BE12 value, then padding */ |
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status = get_unaligned_be16(&req->sample[1]); |
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status = status >> 3; |
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status &= 0x0fff; |
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} |
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kfree(req); |
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return status; |
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} |
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#if IS_ENABLED(CONFIG_HWMON) |
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#define SHOW(name, var, adjust) static ssize_t \ |
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name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ |
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{ \ |
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struct ads7846 *ts = dev_get_drvdata(dev); \ |
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ssize_t v = ads7846_read12_ser(&ts->spi->dev, \ |
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READ_12BIT_SER(var)); \ |
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if (v < 0) \ |
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return v; \ |
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return sprintf(buf, "%u\n", adjust(ts, v)); \ |
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} \ |
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static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); |
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|
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/* Sysfs conventions report temperatures in millidegrees Celsius. |
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* ADS7846 could use the low-accuracy two-sample scheme, but can't do the high |
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* accuracy scheme without calibration data. For now we won't try either; |
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* userspace sees raw sensor values, and must scale/calibrate appropriately. |
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*/ |
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static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v) |
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{ |
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return v; |
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} |
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SHOW(temp0, temp0, null_adjust) /* temp1_input */ |
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SHOW(temp1, temp1, null_adjust) /* temp2_input */ |
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|
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/* sysfs conventions report voltages in millivolts. We can convert voltages |
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* if we know vREF. userspace may need to scale vAUX to match the board's |
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* external resistors; we assume that vBATT only uses the internal ones. |
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*/ |
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static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v) |
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{ |
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unsigned retval = v; |
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|
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/* external resistors may scale vAUX into 0..vREF */ |
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retval *= ts->vref_mv; |
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retval = retval >> 12; |
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|
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return retval; |
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} |
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static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v) |
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{ |
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unsigned retval = vaux_adjust(ts, v); |
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|
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/* ads7846 has a resistor ladder to scale this signal down */ |
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if (ts->model == 7846) |
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retval *= 4; |
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return retval; |
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} |
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SHOW(in0_input, vaux, vaux_adjust) |
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SHOW(in1_input, vbatt, vbatt_adjust) |
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static umode_t ads7846_is_visible(struct kobject *kobj, struct attribute *attr, |
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int index) |
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{ |
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struct device *dev = kobj_to_dev(kobj); |
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struct ads7846 *ts = dev_get_drvdata(dev); |
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if (ts->model == 7843 && index < 2) /* in0, in1 */ |
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return 0; |
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if (ts->model == 7845 && index != 2) /* in0 */ |
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return 0; |
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|
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return attr->mode; |
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} |
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|
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static struct attribute *ads7846_attributes[] = { |
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&dev_attr_temp0.attr, /* 0 */ |
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&dev_attr_temp1.attr, /* 1 */ |
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&dev_attr_in0_input.attr, /* 2 */ |
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&dev_attr_in1_input.attr, /* 3 */ |
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NULL, |
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}; |
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|
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static const struct attribute_group ads7846_attr_group = { |
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.attrs = ads7846_attributes, |
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.is_visible = ads7846_is_visible, |
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}; |
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__ATTRIBUTE_GROUPS(ads7846_attr); |
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|
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static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts) |
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{ |
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/* hwmon sensors need a reference voltage */ |
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switch (ts->model) { |
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case 7846: |
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if (!ts->vref_mv) { |
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dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n"); |
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ts->vref_mv = 2500; |
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ts->use_internal = true; |
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} |
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break; |
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case 7845: |
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case 7843: |
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if (!ts->vref_mv) { |
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dev_warn(&spi->dev, |
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"external vREF for ADS%d not specified\n", |
|
ts->model); |
|
return 0; |
|
} |
|
break; |
|
} |
|
|
|
ts->hwmon = hwmon_device_register_with_groups(&spi->dev, spi->modalias, |
|
ts, ads7846_attr_groups); |
|
|
|
return PTR_ERR_OR_ZERO(ts->hwmon); |
|
} |
|
|
|
static void ads784x_hwmon_unregister(struct spi_device *spi, |
|
struct ads7846 *ts) |
|
{ |
|
if (ts->hwmon) |
|
hwmon_device_unregister(ts->hwmon); |
|
} |
|
|
|
#else |
|
static inline int ads784x_hwmon_register(struct spi_device *spi, |
|
struct ads7846 *ts) |
|
{ |
|
return 0; |
|
} |
|
|
|
static inline void ads784x_hwmon_unregister(struct spi_device *spi, |
|
struct ads7846 *ts) |
|
{ |
|
} |
|
#endif |
|
|
|
static ssize_t ads7846_pen_down_show(struct device *dev, |
|
struct device_attribute *attr, char *buf) |
|
{ |
|
struct ads7846 *ts = dev_get_drvdata(dev); |
|
|
|
return sprintf(buf, "%u\n", ts->pendown); |
|
} |
|
|
|
static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL); |
|
|
|
static ssize_t ads7846_disable_show(struct device *dev, |
|
struct device_attribute *attr, char *buf) |
|
{ |
|
struct ads7846 *ts = dev_get_drvdata(dev); |
|
|
|
return sprintf(buf, "%u\n", ts->disabled); |
|
} |
|
|
|
static ssize_t ads7846_disable_store(struct device *dev, |
|
struct device_attribute *attr, |
|
const char *buf, size_t count) |
|
{ |
|
struct ads7846 *ts = dev_get_drvdata(dev); |
|
unsigned int i; |
|
int err; |
|
|
|
err = kstrtouint(buf, 10, &i); |
|
if (err) |
|
return err; |
|
|
|
if (i) |
|
ads7846_disable(ts); |
|
else |
|
ads7846_enable(ts); |
|
|
|
return count; |
|
} |
|
|
|
static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store); |
|
|
|
static struct attribute *ads784x_attributes[] = { |
|
&dev_attr_pen_down.attr, |
|
&dev_attr_disable.attr, |
|
NULL, |
|
}; |
|
|
|
static const struct attribute_group ads784x_attr_group = { |
|
.attrs = ads784x_attributes, |
|
}; |
|
|
|
/*--------------------------------------------------------------------------*/ |
|
|
|
static void null_wait_for_sync(void) |
|
{ |
|
} |
|
|
|
static int ads7846_debounce_filter(void *ads, int data_idx, int *val) |
|
{ |
|
struct ads7846 *ts = ads; |
|
|
|
if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) { |
|
/* Start over collecting consistent readings. */ |
|
ts->read_rep = 0; |
|
/* |
|
* Repeat it, if this was the first read or the read |
|
* wasn't consistent enough. |
|
*/ |
|
if (ts->read_cnt < ts->debounce_max) { |
|
ts->last_read = *val; |
|
ts->read_cnt++; |
|
return ADS7846_FILTER_REPEAT; |
|
} else { |
|
/* |
|
* Maximum number of debouncing reached and still |
|
* not enough number of consistent readings. Abort |
|
* the whole sample, repeat it in the next sampling |
|
* period. |
|
*/ |
|
ts->read_cnt = 0; |
|
return ADS7846_FILTER_IGNORE; |
|
} |
|
} else { |
|
if (++ts->read_rep > ts->debounce_rep) { |
|
/* |
|
* Got a good reading for this coordinate, |
|
* go for the next one. |
|
*/ |
|
ts->read_cnt = 0; |
|
ts->read_rep = 0; |
|
return ADS7846_FILTER_OK; |
|
} else { |
|
/* Read more values that are consistent. */ |
|
ts->read_cnt++; |
|
return ADS7846_FILTER_REPEAT; |
|
} |
|
} |
|
} |
|
|
|
static int ads7846_no_filter(void *ads, int data_idx, int *val) |
|
{ |
|
return ADS7846_FILTER_OK; |
|
} |
|
|
|
static int ads7846_get_value(struct ads7846_buf *buf) |
|
{ |
|
int value; |
|
|
|
value = be16_to_cpup(&buf->data); |
|
|
|
/* enforce ADC output is 12 bits width */ |
|
return (value >> 3) & 0xfff; |
|
} |
|
|
|
static void ads7846_set_cmd_val(struct ads7846 *ts, enum ads7846_cmds cmd_idx, |
|
u16 val) |
|
{ |
|
struct ads7846_packet *packet = ts->packet; |
|
|
|
switch (cmd_idx) { |
|
case ADS7846_Y: |
|
packet->y = val; |
|
break; |
|
case ADS7846_X: |
|
packet->x = val; |
|
break; |
|
case ADS7846_Z1: |
|
packet->z1 = val; |
|
break; |
|
case ADS7846_Z2: |
|
packet->z2 = val; |
|
break; |
|
default: |
|
WARN_ON_ONCE(1); |
|
} |
|
} |
|
|
|
static u8 ads7846_get_cmd(enum ads7846_cmds cmd_idx, int vref) |
|
{ |
|
switch (cmd_idx) { |
|
case ADS7846_Y: |
|
return READ_Y(vref); |
|
case ADS7846_X: |
|
return READ_X(vref); |
|
|
|
/* 7846 specific commands */ |
|
case ADS7846_Z1: |
|
return READ_Z1(vref); |
|
case ADS7846_Z2: |
|
return READ_Z2(vref); |
|
case ADS7846_PWDOWN: |
|
return PWRDOWN; |
|
default: |
|
WARN_ON_ONCE(1); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static bool ads7846_cmd_need_settle(enum ads7846_cmds cmd_idx) |
|
{ |
|
switch (cmd_idx) { |
|
case ADS7846_X: |
|
case ADS7846_Y: |
|
case ADS7846_Z1: |
|
case ADS7846_Z2: |
|
return true; |
|
case ADS7846_PWDOWN: |
|
return false; |
|
default: |
|
WARN_ON_ONCE(1); |
|
} |
|
|
|
return false; |
|
} |
|
|
|
static int ads7846_filter(struct ads7846 *ts) |
|
{ |
|
struct ads7846_packet *packet = ts->packet; |
|
int action; |
|
int val; |
|
unsigned int cmd_idx, b; |
|
|
|
packet->ignore = false; |
|
for (cmd_idx = packet->last_cmd_idx; cmd_idx < packet->cmds - 1; cmd_idx++) { |
|
struct ads7846_buf_layout *l = &packet->l[cmd_idx]; |
|
|
|
packet->last_cmd_idx = cmd_idx; |
|
|
|
for (b = l->skip; b < l->count; b++) { |
|
val = ads7846_get_value(&packet->rx[l->offset + b]); |
|
|
|
action = ts->filter(ts->filter_data, cmd_idx, &val); |
|
if (action == ADS7846_FILTER_REPEAT) { |
|
if (b == l->count - 1) |
|
return -EAGAIN; |
|
} else if (action == ADS7846_FILTER_OK) { |
|
ads7846_set_cmd_val(ts, cmd_idx, val); |
|
break; |
|
} else { |
|
packet->ignore = true; |
|
return 0; |
|
} |
|
} |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static void ads7846_read_state(struct ads7846 *ts) |
|
{ |
|
struct ads7846_packet *packet = ts->packet; |
|
struct spi_message *m; |
|
int msg_idx = 0; |
|
int error; |
|
|
|
packet->last_cmd_idx = 0; |
|
|
|
while (true) { |
|
ts->wait_for_sync(); |
|
|
|
m = &ts->msg[msg_idx]; |
|
error = spi_sync(ts->spi, m); |
|
if (error) { |
|
dev_err(&ts->spi->dev, "spi_sync --> %d\n", error); |
|
packet->ignore = true; |
|
return; |
|
} |
|
|
|
error = ads7846_filter(ts); |
|
if (error) |
|
continue; |
|
|
|
return; |
|
} |
|
} |
|
|
|
static void ads7846_report_state(struct ads7846 *ts) |
|
{ |
|
struct ads7846_packet *packet = ts->packet; |
|
unsigned int Rt; |
|
u16 x, y, z1, z2; |
|
|
|
x = packet->x; |
|
y = packet->y; |
|
if (ts->model == 7845) { |
|
z1 = 0; |
|
z2 = 0; |
|
} else { |
|
z1 = packet->z1; |
|
z2 = packet->z2; |
|
} |
|
|
|
/* range filtering */ |
|
if (x == MAX_12BIT) |
|
x = 0; |
|
|
|
if (ts->model == 7843) { |
|
Rt = ts->pressure_max / 2; |
|
} else if (ts->model == 7845) { |
|
if (get_pendown_state(ts)) |
|
Rt = ts->pressure_max / 2; |
|
else |
|
Rt = 0; |
|
dev_vdbg(&ts->spi->dev, "x/y: %d/%d, PD %d\n", x, y, Rt); |
|
} else if (likely(x && z1)) { |
|
/* compute touch pressure resistance using equation #2 */ |
|
Rt = z2; |
|
Rt -= z1; |
|
Rt *= ts->x_plate_ohms; |
|
Rt = DIV_ROUND_CLOSEST(Rt, 16); |
|
Rt *= x; |
|
Rt /= z1; |
|
Rt = DIV_ROUND_CLOSEST(Rt, 256); |
|
} else { |
|
Rt = 0; |
|
} |
|
|
|
/* |
|
* Sample found inconsistent by debouncing or pressure is beyond |
|
* the maximum. Don't report it to user space, repeat at least |
|
* once more the measurement |
|
*/ |
|
if (packet->ignore || Rt > ts->pressure_max) { |
|
dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n", |
|
packet->ignore, Rt); |
|
return; |
|
} |
|
|
|
/* |
|
* Maybe check the pendown state before reporting. This discards |
|
* false readings when the pen is lifted. |
|
*/ |
|
if (ts->penirq_recheck_delay_usecs) { |
|
udelay(ts->penirq_recheck_delay_usecs); |
|
if (!get_pendown_state(ts)) |
|
Rt = 0; |
|
} |
|
|
|
/* |
|
* NOTE: We can't rely on the pressure to determine the pen down |
|
* state, even this controller has a pressure sensor. The pressure |
|
* value can fluctuate for quite a while after lifting the pen and |
|
* in some cases may not even settle at the expected value. |
|
* |
|
* The only safe way to check for the pen up condition is in the |
|
* timer by reading the pen signal state (it's a GPIO _and_ IRQ). |
|
*/ |
|
if (Rt) { |
|
struct input_dev *input = ts->input; |
|
|
|
if (!ts->pendown) { |
|
input_report_key(input, BTN_TOUCH, 1); |
|
ts->pendown = true; |
|
dev_vdbg(&ts->spi->dev, "DOWN\n"); |
|
} |
|
|
|
touchscreen_report_pos(input, &ts->core_prop, x, y, false); |
|
input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt); |
|
|
|
input_sync(input); |
|
dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt); |
|
} |
|
} |
|
|
|
static irqreturn_t ads7846_hard_irq(int irq, void *handle) |
|
{ |
|
struct ads7846 *ts = handle; |
|
|
|
return get_pendown_state(ts) ? IRQ_WAKE_THREAD : IRQ_HANDLED; |
|
} |
|
|
|
|
|
static irqreturn_t ads7846_irq(int irq, void *handle) |
|
{ |
|
struct ads7846 *ts = handle; |
|
|
|
/* Start with a small delay before checking pendown state */ |
|
msleep(TS_POLL_DELAY); |
|
|
|
while (!ts->stopped && get_pendown_state(ts)) { |
|
|
|
/* pen is down, continue with the measurement */ |
|
ads7846_read_state(ts); |
|
|
|
if (!ts->stopped) |
|
ads7846_report_state(ts); |
|
|
|
wait_event_timeout(ts->wait, ts->stopped, |
|
msecs_to_jiffies(TS_POLL_PERIOD)); |
|
} |
|
|
|
if (ts->pendown && !ts->stopped) |
|
ads7846_report_pen_up(ts); |
|
|
|
return IRQ_HANDLED; |
|
} |
|
|
|
static int __maybe_unused ads7846_suspend(struct device *dev) |
|
{ |
|
struct ads7846 *ts = dev_get_drvdata(dev); |
|
|
|
mutex_lock(&ts->lock); |
|
|
|
if (!ts->suspended) { |
|
|
|
if (!ts->disabled) |
|
__ads7846_disable(ts); |
|
|
|
if (device_may_wakeup(&ts->spi->dev)) |
|
enable_irq_wake(ts->spi->irq); |
|
|
|
ts->suspended = true; |
|
} |
|
|
|
mutex_unlock(&ts->lock); |
|
|
|
return 0; |
|
} |
|
|
|
static int __maybe_unused ads7846_resume(struct device *dev) |
|
{ |
|
struct ads7846 *ts = dev_get_drvdata(dev); |
|
|
|
mutex_lock(&ts->lock); |
|
|
|
if (ts->suspended) { |
|
|
|
ts->suspended = false; |
|
|
|
if (device_may_wakeup(&ts->spi->dev)) |
|
disable_irq_wake(ts->spi->irq); |
|
|
|
if (!ts->disabled) |
|
__ads7846_enable(ts); |
|
} |
|
|
|
mutex_unlock(&ts->lock); |
|
|
|
return 0; |
|
} |
|
|
|
static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume); |
|
|
|
static int ads7846_setup_pendown(struct spi_device *spi, |
|
struct ads7846 *ts, |
|
const struct ads7846_platform_data *pdata) |
|
{ |
|
int err; |
|
|
|
/* |
|
* REVISIT when the irq can be triggered active-low, or if for some |
|
* reason the touchscreen isn't hooked up, we don't need to access |
|
* the pendown state. |
|
*/ |
|
|
|
if (pdata->get_pendown_state) { |
|
ts->get_pendown_state = pdata->get_pendown_state; |
|
} else if (gpio_is_valid(pdata->gpio_pendown)) { |
|
|
|
err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN, |
|
"ads7846_pendown"); |
|
if (err) { |
|
dev_err(&spi->dev, |
|
"failed to request/setup pendown GPIO%d: %d\n", |
|
pdata->gpio_pendown, err); |
|
return err; |
|
} |
|
|
|
ts->gpio_pendown = pdata->gpio_pendown; |
|
|
|
if (pdata->gpio_pendown_debounce) |
|
gpio_set_debounce(pdata->gpio_pendown, |
|
pdata->gpio_pendown_debounce); |
|
} else { |
|
dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n"); |
|
return -EINVAL; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* Set up the transfers to read touchscreen state; this assumes we |
|
* use formula #2 for pressure, not #3. |
|
*/ |
|
static int ads7846_setup_spi_msg(struct ads7846 *ts, |
|
const struct ads7846_platform_data *pdata) |
|
{ |
|
struct spi_message *m = &ts->msg[0]; |
|
struct spi_transfer *x = ts->xfer; |
|
struct ads7846_packet *packet = ts->packet; |
|
int vref = pdata->keep_vref_on; |
|
unsigned int count, offset = 0; |
|
unsigned int cmd_idx, b; |
|
unsigned long time; |
|
size_t size = 0; |
|
|
|
/* time per bit */ |
|
time = NSEC_PER_SEC / ts->spi->max_speed_hz; |
|
|
|
count = pdata->settle_delay_usecs * NSEC_PER_USEC / time; |
|
packet->count_skip = DIV_ROUND_UP(count, 24); |
|
|
|
if (ts->debounce_max && ts->debounce_rep) |
|
/* ads7846_debounce_filter() is making ts->debounce_rep + 2 |
|
* reads. So we need to get all samples for normal case. */ |
|
packet->count = ts->debounce_rep + 2; |
|
else |
|
packet->count = 1; |
|
|
|
if (ts->model == 7846) |
|
packet->cmds = 5; /* x, y, z1, z2, pwdown */ |
|
else |
|
packet->cmds = 3; /* x, y, pwdown */ |
|
|
|
for (cmd_idx = 0; cmd_idx < packet->cmds; cmd_idx++) { |
|
struct ads7846_buf_layout *l = &packet->l[cmd_idx]; |
|
unsigned int max_count; |
|
|
|
if (ads7846_cmd_need_settle(cmd_idx)) |
|
max_count = packet->count + packet->count_skip; |
|
else |
|
max_count = packet->count; |
|
|
|
l->offset = offset; |
|
offset += max_count; |
|
l->count = max_count; |
|
l->skip = packet->count_skip; |
|
size += sizeof(*packet->tx) * max_count; |
|
} |
|
|
|
packet->tx = devm_kzalloc(&ts->spi->dev, size, GFP_KERNEL); |
|
if (!packet->tx) |
|
return -ENOMEM; |
|
|
|
packet->rx = devm_kzalloc(&ts->spi->dev, size, GFP_KERNEL); |
|
if (!packet->rx) |
|
return -ENOMEM; |
|
|
|
if (ts->model == 7873) { |
|
/* |
|
* The AD7873 is almost identical to the ADS7846 |
|
* keep VREF off during differential/ratiometric |
|
* conversion modes. |
|
*/ |
|
ts->model = 7846; |
|
vref = 0; |
|
} |
|
|
|
ts->msg_count = 1; |
|
spi_message_init(m); |
|
m->context = ts; |
|
|
|
for (cmd_idx = 0; cmd_idx < packet->cmds; cmd_idx++) { |
|
struct ads7846_buf_layout *l = &packet->l[cmd_idx]; |
|
u8 cmd = ads7846_get_cmd(cmd_idx, vref); |
|
|
|
for (b = 0; b < l->count; b++) |
|
packet->tx[l->offset + b].cmd = cmd; |
|
} |
|
|
|
x->tx_buf = packet->tx; |
|
x->rx_buf = packet->rx; |
|
x->len = size; |
|
spi_message_add_tail(x, m); |
|
|
|
return 0; |
|
} |
|
|
|
#ifdef CONFIG_OF |
|
static const struct of_device_id ads7846_dt_ids[] = { |
|
{ .compatible = "ti,tsc2046", .data = (void *) 7846 }, |
|
{ .compatible = "ti,ads7843", .data = (void *) 7843 }, |
|
{ .compatible = "ti,ads7845", .data = (void *) 7845 }, |
|
{ .compatible = "ti,ads7846", .data = (void *) 7846 }, |
|
{ .compatible = "ti,ads7873", .data = (void *) 7873 }, |
|
{ } |
|
}; |
|
MODULE_DEVICE_TABLE(of, ads7846_dt_ids); |
|
|
|
static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev) |
|
{ |
|
struct ads7846_platform_data *pdata; |
|
struct device_node *node = dev->of_node; |
|
const struct of_device_id *match; |
|
u32 value; |
|
|
|
if (!node) { |
|
dev_err(dev, "Device does not have associated DT data\n"); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
|
|
match = of_match_device(ads7846_dt_ids, dev); |
|
if (!match) { |
|
dev_err(dev, "Unknown device model\n"); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
|
|
pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); |
|
if (!pdata) |
|
return ERR_PTR(-ENOMEM); |
|
|
|
pdata->model = (unsigned long)match->data; |
|
|
|
of_property_read_u16(node, "ti,vref-delay-usecs", |
|
&pdata->vref_delay_usecs); |
|
of_property_read_u16(node, "ti,vref-mv", &pdata->vref_mv); |
|
pdata->keep_vref_on = of_property_read_bool(node, "ti,keep-vref-on"); |
|
|
|
pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy"); |
|
|
|
of_property_read_u16(node, "ti,settle-delay-usec", |
|
&pdata->settle_delay_usecs); |
|
of_property_read_u16(node, "ti,penirq-recheck-delay-usecs", |
|
&pdata->penirq_recheck_delay_usecs); |
|
|
|
of_property_read_u16(node, "ti,x-plate-ohms", &pdata->x_plate_ohms); |
|
of_property_read_u16(node, "ti,y-plate-ohms", &pdata->y_plate_ohms); |
|
|
|
of_property_read_u16(node, "ti,x-min", &pdata->x_min); |
|
of_property_read_u16(node, "ti,y-min", &pdata->y_min); |
|
of_property_read_u16(node, "ti,x-max", &pdata->x_max); |
|
of_property_read_u16(node, "ti,y-max", &pdata->y_max); |
|
|
|
/* |
|
* touchscreen-max-pressure gets parsed during |
|
* touchscreen_parse_properties() |
|
*/ |
|
of_property_read_u16(node, "ti,pressure-min", &pdata->pressure_min); |
|
if (!of_property_read_u32(node, "touchscreen-min-pressure", &value)) |
|
pdata->pressure_min = (u16) value; |
|
of_property_read_u16(node, "ti,pressure-max", &pdata->pressure_max); |
|
|
|
of_property_read_u16(node, "ti,debounce-max", &pdata->debounce_max); |
|
if (!of_property_read_u32(node, "touchscreen-average-samples", &value)) |
|
pdata->debounce_max = (u16) value; |
|
of_property_read_u16(node, "ti,debounce-tol", &pdata->debounce_tol); |
|
of_property_read_u16(node, "ti,debounce-rep", &pdata->debounce_rep); |
|
|
|
of_property_read_u32(node, "ti,pendown-gpio-debounce", |
|
&pdata->gpio_pendown_debounce); |
|
|
|
pdata->wakeup = of_property_read_bool(node, "wakeup-source") || |
|
of_property_read_bool(node, "linux,wakeup"); |
|
|
|
pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0); |
|
|
|
return pdata; |
|
} |
|
#else |
|
static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev) |
|
{ |
|
dev_err(dev, "no platform data defined\n"); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
#endif |
|
|
|
static int ads7846_probe(struct spi_device *spi) |
|
{ |
|
const struct ads7846_platform_data *pdata; |
|
struct ads7846 *ts; |
|
struct ads7846_packet *packet; |
|
struct input_dev *input_dev; |
|
unsigned long irq_flags; |
|
int err; |
|
|
|
if (!spi->irq) { |
|
dev_dbg(&spi->dev, "no IRQ?\n"); |
|
return -EINVAL; |
|
} |
|
|
|
/* don't exceed max specified sample rate */ |
|
if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) { |
|
dev_err(&spi->dev, "f(sample) %d KHz?\n", |
|
(spi->max_speed_hz/SAMPLE_BITS)/1000); |
|
return -EINVAL; |
|
} |
|
|
|
/* |
|
* We'd set TX word size 8 bits and RX word size to 13 bits ... except |
|
* that even if the hardware can do that, the SPI controller driver |
|
* may not. So we stick to very-portable 8 bit words, both RX and TX. |
|
*/ |
|
spi->bits_per_word = 8; |
|
spi->mode &= ~SPI_MODE_X_MASK; |
|
spi->mode |= SPI_MODE_0; |
|
err = spi_setup(spi); |
|
if (err < 0) |
|
return err; |
|
|
|
ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); |
|
packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL); |
|
input_dev = input_allocate_device(); |
|
if (!ts || !packet || !input_dev) { |
|
err = -ENOMEM; |
|
goto err_free_mem; |
|
} |
|
|
|
spi_set_drvdata(spi, ts); |
|
|
|
ts->packet = packet; |
|
ts->spi = spi; |
|
ts->input = input_dev; |
|
|
|
mutex_init(&ts->lock); |
|
init_waitqueue_head(&ts->wait); |
|
|
|
pdata = dev_get_platdata(&spi->dev); |
|
if (!pdata) { |
|
pdata = ads7846_probe_dt(&spi->dev); |
|
if (IS_ERR(pdata)) { |
|
err = PTR_ERR(pdata); |
|
goto err_free_mem; |
|
} |
|
} |
|
|
|
ts->model = pdata->model ? : 7846; |
|
ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; |
|
ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; |
|
ts->vref_mv = pdata->vref_mv; |
|
|
|
if (pdata->filter != NULL) { |
|
if (pdata->filter_init != NULL) { |
|
err = pdata->filter_init(pdata, &ts->filter_data); |
|
if (err < 0) |
|
goto err_free_mem; |
|
} |
|
ts->filter = pdata->filter; |
|
ts->filter_cleanup = pdata->filter_cleanup; |
|
} else if (pdata->debounce_max) { |
|
ts->debounce_max = pdata->debounce_max; |
|
if (ts->debounce_max < 2) |
|
ts->debounce_max = 2; |
|
ts->debounce_tol = pdata->debounce_tol; |
|
ts->debounce_rep = pdata->debounce_rep; |
|
ts->filter = ads7846_debounce_filter; |
|
ts->filter_data = ts; |
|
} else { |
|
ts->filter = ads7846_no_filter; |
|
} |
|
|
|
err = ads7846_setup_pendown(spi, ts, pdata); |
|
if (err) |
|
goto err_cleanup_filter; |
|
|
|
if (pdata->penirq_recheck_delay_usecs) |
|
ts->penirq_recheck_delay_usecs = |
|
pdata->penirq_recheck_delay_usecs; |
|
|
|
ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync; |
|
|
|
snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); |
|
snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model); |
|
|
|
input_dev->name = ts->name; |
|
input_dev->phys = ts->phys; |
|
input_dev->dev.parent = &spi->dev; |
|
|
|
input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); |
|
input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); |
|
input_set_abs_params(input_dev, ABS_X, |
|
pdata->x_min ? : 0, |
|
pdata->x_max ? : MAX_12BIT, |
|
0, 0); |
|
input_set_abs_params(input_dev, ABS_Y, |
|
pdata->y_min ? : 0, |
|
pdata->y_max ? : MAX_12BIT, |
|
0, 0); |
|
input_set_abs_params(input_dev, ABS_PRESSURE, |
|
pdata->pressure_min, pdata->pressure_max, 0, 0); |
|
|
|
/* |
|
* Parse common framework properties. Must be done here to ensure the |
|
* correct behaviour in case of using the legacy vendor bindings. The |
|
* general binding value overrides the vendor specific one. |
|
*/ |
|
touchscreen_parse_properties(ts->input, false, &ts->core_prop); |
|
ts->pressure_max = input_abs_get_max(input_dev, ABS_PRESSURE) ? : ~0; |
|
|
|
/* |
|
* Check if legacy ti,swap-xy binding is used instead of |
|
* touchscreen-swapped-x-y |
|
*/ |
|
if (!ts->core_prop.swap_x_y && pdata->swap_xy) { |
|
swap(input_dev->absinfo[ABS_X], input_dev->absinfo[ABS_Y]); |
|
ts->core_prop.swap_x_y = true; |
|
} |
|
|
|
ads7846_setup_spi_msg(ts, pdata); |
|
|
|
ts->reg = regulator_get(&spi->dev, "vcc"); |
|
if (IS_ERR(ts->reg)) { |
|
err = PTR_ERR(ts->reg); |
|
dev_err(&spi->dev, "unable to get regulator: %d\n", err); |
|
goto err_free_gpio; |
|
} |
|
|
|
err = regulator_enable(ts->reg); |
|
if (err) { |
|
dev_err(&spi->dev, "unable to enable regulator: %d\n", err); |
|
goto err_put_regulator; |
|
} |
|
|
|
irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING; |
|
irq_flags |= IRQF_ONESHOT; |
|
|
|
err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq, |
|
irq_flags, spi->dev.driver->name, ts); |
|
if (err && !pdata->irq_flags) { |
|
dev_info(&spi->dev, |
|
"trying pin change workaround on irq %d\n", spi->irq); |
|
irq_flags |= IRQF_TRIGGER_RISING; |
|
err = request_threaded_irq(spi->irq, |
|
ads7846_hard_irq, ads7846_irq, |
|
irq_flags, spi->dev.driver->name, ts); |
|
} |
|
|
|
if (err) { |
|
dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); |
|
goto err_disable_regulator; |
|
} |
|
|
|
err = ads784x_hwmon_register(spi, ts); |
|
if (err) |
|
goto err_free_irq; |
|
|
|
dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq); |
|
|
|
/* |
|
* Take a first sample, leaving nPENIRQ active and vREF off; avoid |
|
* the touchscreen, in case it's not connected. |
|
*/ |
|
if (ts->model == 7845) |
|
ads7845_read12_ser(&spi->dev, PWRDOWN); |
|
else |
|
(void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux)); |
|
|
|
err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group); |
|
if (err) |
|
goto err_remove_hwmon; |
|
|
|
err = input_register_device(input_dev); |
|
if (err) |
|
goto err_remove_attr_group; |
|
|
|
device_init_wakeup(&spi->dev, pdata->wakeup); |
|
|
|
/* |
|
* If device does not carry platform data we must have allocated it |
|
* when parsing DT data. |
|
*/ |
|
if (!dev_get_platdata(&spi->dev)) |
|
devm_kfree(&spi->dev, (void *)pdata); |
|
|
|
return 0; |
|
|
|
err_remove_attr_group: |
|
sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); |
|
err_remove_hwmon: |
|
ads784x_hwmon_unregister(spi, ts); |
|
err_free_irq: |
|
free_irq(spi->irq, ts); |
|
err_disable_regulator: |
|
regulator_disable(ts->reg); |
|
err_put_regulator: |
|
regulator_put(ts->reg); |
|
err_free_gpio: |
|
if (!ts->get_pendown_state) |
|
gpio_free(ts->gpio_pendown); |
|
err_cleanup_filter: |
|
if (ts->filter_cleanup) |
|
ts->filter_cleanup(ts->filter_data); |
|
err_free_mem: |
|
input_free_device(input_dev); |
|
kfree(packet); |
|
kfree(ts); |
|
return err; |
|
} |
|
|
|
static int ads7846_remove(struct spi_device *spi) |
|
{ |
|
struct ads7846 *ts = spi_get_drvdata(spi); |
|
|
|
sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); |
|
|
|
ads7846_disable(ts); |
|
free_irq(ts->spi->irq, ts); |
|
|
|
input_unregister_device(ts->input); |
|
|
|
ads784x_hwmon_unregister(spi, ts); |
|
|
|
regulator_put(ts->reg); |
|
|
|
if (!ts->get_pendown_state) { |
|
/* |
|
* If we are not using specialized pendown method we must |
|
* have been relying on gpio we set up ourselves. |
|
*/ |
|
gpio_free(ts->gpio_pendown); |
|
} |
|
|
|
if (ts->filter_cleanup) |
|
ts->filter_cleanup(ts->filter_data); |
|
|
|
kfree(ts->packet); |
|
kfree(ts); |
|
|
|
dev_dbg(&spi->dev, "unregistered touchscreen\n"); |
|
|
|
return 0; |
|
} |
|
|
|
static struct spi_driver ads7846_driver = { |
|
.driver = { |
|
.name = "ads7846", |
|
.pm = &ads7846_pm, |
|
.of_match_table = of_match_ptr(ads7846_dt_ids), |
|
}, |
|
.probe = ads7846_probe, |
|
.remove = ads7846_remove, |
|
}; |
|
|
|
module_spi_driver(ads7846_driver); |
|
|
|
MODULE_DESCRIPTION("ADS7846 TouchScreen Driver"); |
|
MODULE_LICENSE("GPL"); |
|
MODULE_ALIAS("spi:ads7846");
|
|
|