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776 lines
17 KiB
776 lines
17 KiB
// SPDX-License-Identifier: GPL-2.0+ |
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/* |
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* FSI-attached I2C master algorithm |
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* |
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* Copyright 2018 IBM Corporation |
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* |
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* This program is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU General Public License |
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* as published by the Free Software Foundation; either version |
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* 2 of the License, or (at your option) any later version. |
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*/ |
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#include <linux/bitfield.h> |
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#include <linux/bitops.h> |
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#include <linux/delay.h> |
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#include <linux/device.h> |
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#include <linux/errno.h> |
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#include <linux/fsi.h> |
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#include <linux/i2c.h> |
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#include <linux/jiffies.h> |
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#include <linux/kernel.h> |
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#include <linux/list.h> |
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#include <linux/module.h> |
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#include <linux/mutex.h> |
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#include <linux/of.h> |
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#include <linux/slab.h> |
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#define FSI_ENGID_I2C 0x7 |
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#define I2C_DEFAULT_CLK_DIV 6 |
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/* i2c registers */ |
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#define I2C_FSI_FIFO 0x00 |
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#define I2C_FSI_CMD 0x04 |
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#define I2C_FSI_MODE 0x08 |
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#define I2C_FSI_WATER_MARK 0x0C |
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#define I2C_FSI_INT_MASK 0x10 |
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#define I2C_FSI_INT_COND 0x14 |
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#define I2C_FSI_OR_INT_MASK 0x14 |
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#define I2C_FSI_INTS 0x18 |
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#define I2C_FSI_AND_INT_MASK 0x18 |
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#define I2C_FSI_STAT 0x1C |
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#define I2C_FSI_RESET_I2C 0x1C |
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#define I2C_FSI_ESTAT 0x20 |
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#define I2C_FSI_RESET_ERR 0x20 |
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#define I2C_FSI_RESID_LEN 0x24 |
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#define I2C_FSI_SET_SCL 0x24 |
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#define I2C_FSI_PORT_BUSY 0x28 |
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#define I2C_FSI_RESET_SCL 0x2C |
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#define I2C_FSI_SET_SDA 0x30 |
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#define I2C_FSI_RESET_SDA 0x34 |
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/* cmd register */ |
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#define I2C_CMD_WITH_START BIT(31) |
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#define I2C_CMD_WITH_ADDR BIT(30) |
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#define I2C_CMD_RD_CONT BIT(29) |
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#define I2C_CMD_WITH_STOP BIT(28) |
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#define I2C_CMD_FORCELAUNCH BIT(27) |
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#define I2C_CMD_ADDR GENMASK(23, 17) |
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#define I2C_CMD_READ BIT(16) |
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#define I2C_CMD_LEN GENMASK(15, 0) |
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/* mode register */ |
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#define I2C_MODE_CLKDIV GENMASK(31, 16) |
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#define I2C_MODE_PORT GENMASK(15, 10) |
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#define I2C_MODE_ENHANCED BIT(3) |
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#define I2C_MODE_DIAG BIT(2) |
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#define I2C_MODE_PACE_ALLOW BIT(1) |
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#define I2C_MODE_WRAP BIT(0) |
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/* watermark register */ |
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#define I2C_WATERMARK_HI GENMASK(15, 12) |
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#define I2C_WATERMARK_LO GENMASK(7, 4) |
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#define I2C_FIFO_HI_LVL 4 |
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#define I2C_FIFO_LO_LVL 4 |
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/* interrupt register */ |
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#define I2C_INT_INV_CMD BIT(15) |
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#define I2C_INT_PARITY BIT(14) |
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#define I2C_INT_BE_OVERRUN BIT(13) |
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#define I2C_INT_BE_ACCESS BIT(12) |
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#define I2C_INT_LOST_ARB BIT(11) |
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#define I2C_INT_NACK BIT(10) |
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#define I2C_INT_DAT_REQ BIT(9) |
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#define I2C_INT_CMD_COMP BIT(8) |
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#define I2C_INT_STOP_ERR BIT(7) |
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#define I2C_INT_BUSY BIT(6) |
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#define I2C_INT_IDLE BIT(5) |
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/* status register */ |
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#define I2C_STAT_INV_CMD BIT(31) |
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#define I2C_STAT_PARITY BIT(30) |
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#define I2C_STAT_BE_OVERRUN BIT(29) |
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#define I2C_STAT_BE_ACCESS BIT(28) |
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#define I2C_STAT_LOST_ARB BIT(27) |
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#define I2C_STAT_NACK BIT(26) |
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#define I2C_STAT_DAT_REQ BIT(25) |
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#define I2C_STAT_CMD_COMP BIT(24) |
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#define I2C_STAT_STOP_ERR BIT(23) |
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#define I2C_STAT_MAX_PORT GENMASK(22, 16) |
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#define I2C_STAT_ANY_INT BIT(15) |
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#define I2C_STAT_SCL_IN BIT(11) |
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#define I2C_STAT_SDA_IN BIT(10) |
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#define I2C_STAT_PORT_BUSY BIT(9) |
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#define I2C_STAT_SELF_BUSY BIT(8) |
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#define I2C_STAT_FIFO_COUNT GENMASK(7, 0) |
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#define I2C_STAT_ERR (I2C_STAT_INV_CMD | \ |
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I2C_STAT_PARITY | \ |
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I2C_STAT_BE_OVERRUN | \ |
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I2C_STAT_BE_ACCESS | \ |
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I2C_STAT_LOST_ARB | \ |
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I2C_STAT_NACK | \ |
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I2C_STAT_STOP_ERR) |
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#define I2C_STAT_ANY_RESP (I2C_STAT_ERR | \ |
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I2C_STAT_DAT_REQ | \ |
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I2C_STAT_CMD_COMP) |
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/* extended status register */ |
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#define I2C_ESTAT_FIFO_SZ GENMASK(31, 24) |
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#define I2C_ESTAT_SCL_IN_SY BIT(15) |
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#define I2C_ESTAT_SDA_IN_SY BIT(14) |
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#define I2C_ESTAT_S_SCL BIT(13) |
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#define I2C_ESTAT_S_SDA BIT(12) |
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#define I2C_ESTAT_M_SCL BIT(11) |
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#define I2C_ESTAT_M_SDA BIT(10) |
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#define I2C_ESTAT_HI_WATER BIT(9) |
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#define I2C_ESTAT_LO_WATER BIT(8) |
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#define I2C_ESTAT_PORT_BUSY BIT(7) |
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#define I2C_ESTAT_SELF_BUSY BIT(6) |
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#define I2C_ESTAT_VERSION GENMASK(4, 0) |
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/* port busy register */ |
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#define I2C_PORT_BUSY_RESET BIT(31) |
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/* wait for command complete or data request */ |
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#define I2C_CMD_SLEEP_MAX_US 500 |
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#define I2C_CMD_SLEEP_MIN_US 50 |
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/* wait after reset; choose time from legacy driver */ |
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#define I2C_RESET_SLEEP_MAX_US 2000 |
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#define I2C_RESET_SLEEP_MIN_US 1000 |
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/* choose timeout length from legacy driver; it's well tested */ |
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#define I2C_ABORT_TIMEOUT msecs_to_jiffies(100) |
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struct fsi_i2c_master { |
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struct fsi_device *fsi; |
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u8 fifo_size; |
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struct list_head ports; |
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struct mutex lock; |
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}; |
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struct fsi_i2c_port { |
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struct list_head list; |
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struct i2c_adapter adapter; |
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struct fsi_i2c_master *master; |
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u16 port; |
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u16 xfrd; |
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}; |
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static int fsi_i2c_read_reg(struct fsi_device *fsi, unsigned int reg, |
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u32 *data) |
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{ |
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int rc; |
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__be32 data_be; |
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rc = fsi_device_read(fsi, reg, &data_be, sizeof(data_be)); |
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if (rc) |
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return rc; |
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*data = be32_to_cpu(data_be); |
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return 0; |
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} |
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static int fsi_i2c_write_reg(struct fsi_device *fsi, unsigned int reg, |
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u32 *data) |
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{ |
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__be32 data_be = cpu_to_be32p(data); |
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return fsi_device_write(fsi, reg, &data_be, sizeof(data_be)); |
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} |
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static int fsi_i2c_dev_init(struct fsi_i2c_master *i2c) |
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{ |
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int rc; |
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u32 mode = I2C_MODE_ENHANCED, extended_status, watermark; |
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u32 interrupt = 0; |
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/* since we use polling, disable interrupts */ |
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_INT_MASK, &interrupt); |
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if (rc) |
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return rc; |
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mode |= FIELD_PREP(I2C_MODE_CLKDIV, I2C_DEFAULT_CLK_DIV); |
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); |
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if (rc) |
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return rc; |
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_ESTAT, &extended_status); |
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if (rc) |
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return rc; |
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i2c->fifo_size = FIELD_GET(I2C_ESTAT_FIFO_SZ, extended_status); |
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watermark = FIELD_PREP(I2C_WATERMARK_HI, |
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i2c->fifo_size - I2C_FIFO_HI_LVL); |
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watermark |= FIELD_PREP(I2C_WATERMARK_LO, I2C_FIFO_LO_LVL); |
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return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_WATER_MARK, &watermark); |
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} |
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static int fsi_i2c_set_port(struct fsi_i2c_port *port) |
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{ |
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int rc; |
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struct fsi_device *fsi = port->master->fsi; |
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u32 mode, dummy = 0; |
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rc = fsi_i2c_read_reg(fsi, I2C_FSI_MODE, &mode); |
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if (rc) |
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return rc; |
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if (FIELD_GET(I2C_MODE_PORT, mode) == port->port) |
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return 0; |
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mode = (mode & ~I2C_MODE_PORT) | FIELD_PREP(I2C_MODE_PORT, port->port); |
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rc = fsi_i2c_write_reg(fsi, I2C_FSI_MODE, &mode); |
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if (rc) |
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return rc; |
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/* reset engine when port is changed */ |
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return fsi_i2c_write_reg(fsi, I2C_FSI_RESET_ERR, &dummy); |
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} |
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static int fsi_i2c_start(struct fsi_i2c_port *port, struct i2c_msg *msg, |
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bool stop) |
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{ |
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struct fsi_i2c_master *i2c = port->master; |
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u32 cmd = I2C_CMD_WITH_START | I2C_CMD_WITH_ADDR; |
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port->xfrd = 0; |
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if (msg->flags & I2C_M_RD) |
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cmd |= I2C_CMD_READ; |
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if (stop || msg->flags & I2C_M_STOP) |
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cmd |= I2C_CMD_WITH_STOP; |
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cmd |= FIELD_PREP(I2C_CMD_ADDR, msg->addr); |
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cmd |= FIELD_PREP(I2C_CMD_LEN, msg->len); |
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return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_CMD, &cmd); |
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} |
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static int fsi_i2c_get_op_bytes(int op_bytes) |
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{ |
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/* fsi is limited to max 4 byte aligned ops */ |
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if (op_bytes > 4) |
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return 4; |
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else if (op_bytes == 3) |
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return 2; |
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return op_bytes; |
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} |
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static int fsi_i2c_write_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg, |
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u8 fifo_count) |
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{ |
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int write; |
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int rc; |
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struct fsi_i2c_master *i2c = port->master; |
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int bytes_to_write = i2c->fifo_size - fifo_count; |
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int bytes_remaining = msg->len - port->xfrd; |
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bytes_to_write = min(bytes_to_write, bytes_remaining); |
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while (bytes_to_write) { |
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write = fsi_i2c_get_op_bytes(bytes_to_write); |
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rc = fsi_device_write(i2c->fsi, I2C_FSI_FIFO, |
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&msg->buf[port->xfrd], write); |
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if (rc) |
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return rc; |
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port->xfrd += write; |
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bytes_to_write -= write; |
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} |
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return 0; |
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} |
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static int fsi_i2c_read_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg, |
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u8 fifo_count) |
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{ |
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int read; |
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int rc; |
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struct fsi_i2c_master *i2c = port->master; |
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int bytes_to_read; |
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int xfr_remaining = msg->len - port->xfrd; |
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u32 dummy; |
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bytes_to_read = min_t(int, fifo_count, xfr_remaining); |
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while (bytes_to_read) { |
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read = fsi_i2c_get_op_bytes(bytes_to_read); |
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if (xfr_remaining) { |
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rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO, |
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&msg->buf[port->xfrd], read); |
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if (rc) |
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return rc; |
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port->xfrd += read; |
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xfr_remaining -= read; |
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} else { |
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/* no more buffer but data in fifo, need to clear it */ |
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rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO, &dummy, |
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read); |
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if (rc) |
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return rc; |
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} |
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bytes_to_read -= read; |
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} |
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return 0; |
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} |
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static int fsi_i2c_get_scl(struct i2c_adapter *adap) |
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{ |
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u32 stat = 0; |
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struct fsi_i2c_port *port = adap->algo_data; |
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struct fsi_i2c_master *i2c = port->master; |
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fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); |
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return !!(stat & I2C_STAT_SCL_IN); |
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} |
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static void fsi_i2c_set_scl(struct i2c_adapter *adap, int val) |
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{ |
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u32 dummy = 0; |
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struct fsi_i2c_port *port = adap->algo_data; |
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struct fsi_i2c_master *i2c = port->master; |
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if (val) |
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_SET_SCL, &dummy); |
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else |
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_SCL, &dummy); |
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} |
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static int fsi_i2c_get_sda(struct i2c_adapter *adap) |
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{ |
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u32 stat = 0; |
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struct fsi_i2c_port *port = adap->algo_data; |
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struct fsi_i2c_master *i2c = port->master; |
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fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); |
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return !!(stat & I2C_STAT_SDA_IN); |
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} |
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static void fsi_i2c_set_sda(struct i2c_adapter *adap, int val) |
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{ |
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u32 dummy = 0; |
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struct fsi_i2c_port *port = adap->algo_data; |
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struct fsi_i2c_master *i2c = port->master; |
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if (val) |
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_SET_SDA, &dummy); |
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else |
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_SDA, &dummy); |
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} |
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static void fsi_i2c_prepare_recovery(struct i2c_adapter *adap) |
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{ |
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int rc; |
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u32 mode; |
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struct fsi_i2c_port *port = adap->algo_data; |
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struct fsi_i2c_master *i2c = port->master; |
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode); |
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if (rc) |
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return; |
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mode |= I2C_MODE_DIAG; |
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); |
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} |
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static void fsi_i2c_unprepare_recovery(struct i2c_adapter *adap) |
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{ |
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int rc; |
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u32 mode; |
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struct fsi_i2c_port *port = adap->algo_data; |
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struct fsi_i2c_master *i2c = port->master; |
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode); |
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if (rc) |
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return; |
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mode &= ~I2C_MODE_DIAG; |
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); |
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} |
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static int fsi_i2c_reset_bus(struct fsi_i2c_master *i2c, |
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struct fsi_i2c_port *port) |
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{ |
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int rc; |
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u32 stat, dummy = 0; |
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/* force bus reset, ignore errors */ |
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i2c_recover_bus(&port->adapter); |
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/* reset errors */ |
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_ERR, &dummy); |
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if (rc) |
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return rc; |
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/* wait for command complete */ |
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usleep_range(I2C_RESET_SLEEP_MIN_US, I2C_RESET_SLEEP_MAX_US); |
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); |
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if (rc) |
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return rc; |
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if (stat & I2C_STAT_CMD_COMP) |
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return 0; |
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/* failed to get command complete; reset engine again */ |
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_I2C, &dummy); |
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if (rc) |
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return rc; |
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/* re-init engine again */ |
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return fsi_i2c_dev_init(i2c); |
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} |
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static int fsi_i2c_reset_engine(struct fsi_i2c_master *i2c, u16 port) |
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{ |
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int rc; |
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u32 mode, dummy = 0; |
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/* reset engine */ |
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_I2C, &dummy); |
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if (rc) |
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return rc; |
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/* re-init engine */ |
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rc = fsi_i2c_dev_init(i2c); |
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if (rc) |
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return rc; |
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode); |
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if (rc) |
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return rc; |
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/* set port; default after reset is 0 */ |
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if (port) { |
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mode &= ~I2C_MODE_PORT; |
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mode |= FIELD_PREP(I2C_MODE_PORT, port); |
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); |
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if (rc) |
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return rc; |
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} |
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/* reset busy register; hw workaround */ |
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dummy = I2C_PORT_BUSY_RESET; |
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_PORT_BUSY, &dummy); |
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if (rc) |
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return rc; |
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return 0; |
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} |
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static int fsi_i2c_abort(struct fsi_i2c_port *port, u32 status) |
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{ |
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int rc; |
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unsigned long start; |
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u32 cmd = I2C_CMD_WITH_STOP; |
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u32 stat; |
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struct fsi_i2c_master *i2c = port->master; |
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struct fsi_device *fsi = i2c->fsi; |
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rc = fsi_i2c_reset_engine(i2c, port->port); |
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if (rc) |
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return rc; |
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rc = fsi_i2c_read_reg(fsi, I2C_FSI_STAT, &stat); |
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if (rc) |
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return rc; |
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/* if sda is low, peform full bus reset */ |
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if (!(stat & I2C_STAT_SDA_IN)) { |
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rc = fsi_i2c_reset_bus(i2c, port); |
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if (rc) |
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return rc; |
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} |
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/* skip final stop command for these errors */ |
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if (status & (I2C_STAT_PARITY | I2C_STAT_LOST_ARB | I2C_STAT_STOP_ERR)) |
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return 0; |
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/* write stop command */ |
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rc = fsi_i2c_write_reg(fsi, I2C_FSI_CMD, &cmd); |
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if (rc) |
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return rc; |
|
|
|
/* wait until we see command complete in the master */ |
|
start = jiffies; |
|
|
|
do { |
|
rc = fsi_i2c_read_reg(fsi, I2C_FSI_STAT, &status); |
|
if (rc) |
|
return rc; |
|
|
|
if (status & I2C_STAT_CMD_COMP) |
|
return 0; |
|
|
|
usleep_range(I2C_CMD_SLEEP_MIN_US, I2C_CMD_SLEEP_MAX_US); |
|
} while (time_after(start + I2C_ABORT_TIMEOUT, jiffies)); |
|
|
|
return -ETIMEDOUT; |
|
} |
|
|
|
static int fsi_i2c_handle_status(struct fsi_i2c_port *port, |
|
struct i2c_msg *msg, u32 status) |
|
{ |
|
int rc; |
|
u8 fifo_count; |
|
|
|
if (status & I2C_STAT_ERR) { |
|
rc = fsi_i2c_abort(port, status); |
|
if (rc) |
|
return rc; |
|
|
|
if (status & I2C_STAT_INV_CMD) |
|
return -EINVAL; |
|
|
|
if (status & (I2C_STAT_PARITY | I2C_STAT_BE_OVERRUN | |
|
I2C_STAT_BE_ACCESS)) |
|
return -EPROTO; |
|
|
|
if (status & I2C_STAT_NACK) |
|
return -ENXIO; |
|
|
|
if (status & I2C_STAT_LOST_ARB) |
|
return -EAGAIN; |
|
|
|
if (status & I2C_STAT_STOP_ERR) |
|
return -EBADMSG; |
|
|
|
return -EIO; |
|
} |
|
|
|
if (status & I2C_STAT_DAT_REQ) { |
|
fifo_count = FIELD_GET(I2C_STAT_FIFO_COUNT, status); |
|
|
|
if (msg->flags & I2C_M_RD) |
|
return fsi_i2c_read_fifo(port, msg, fifo_count); |
|
|
|
return fsi_i2c_write_fifo(port, msg, fifo_count); |
|
} |
|
|
|
if (status & I2C_STAT_CMD_COMP) { |
|
if (port->xfrd < msg->len) |
|
return -ENODATA; |
|
|
|
return msg->len; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int fsi_i2c_wait(struct fsi_i2c_port *port, struct i2c_msg *msg, |
|
unsigned long timeout) |
|
{ |
|
u32 status = 0; |
|
int rc; |
|
unsigned long start = jiffies; |
|
|
|
do { |
|
rc = fsi_i2c_read_reg(port->master->fsi, I2C_FSI_STAT, |
|
&status); |
|
if (rc) |
|
return rc; |
|
|
|
if (status & I2C_STAT_ANY_RESP) { |
|
rc = fsi_i2c_handle_status(port, msg, status); |
|
if (rc < 0) |
|
return rc; |
|
|
|
/* cmd complete and all data xfrd */ |
|
if (rc == msg->len) |
|
return 0; |
|
|
|
/* need to xfr more data, but maybe don't need wait */ |
|
continue; |
|
} |
|
|
|
usleep_range(I2C_CMD_SLEEP_MIN_US, I2C_CMD_SLEEP_MAX_US); |
|
} while (time_after(start + timeout, jiffies)); |
|
|
|
return -ETIMEDOUT; |
|
} |
|
|
|
static int fsi_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, |
|
int num) |
|
{ |
|
int i, rc; |
|
unsigned long start_time; |
|
struct fsi_i2c_port *port = adap->algo_data; |
|
struct fsi_i2c_master *master = port->master; |
|
struct i2c_msg *msg; |
|
|
|
mutex_lock(&master->lock); |
|
|
|
rc = fsi_i2c_set_port(port); |
|
if (rc) |
|
goto unlock; |
|
|
|
for (i = 0; i < num; i++) { |
|
msg = msgs + i; |
|
start_time = jiffies; |
|
|
|
rc = fsi_i2c_start(port, msg, i == num - 1); |
|
if (rc) |
|
goto unlock; |
|
|
|
rc = fsi_i2c_wait(port, msg, |
|
adap->timeout - (jiffies - start_time)); |
|
if (rc) |
|
goto unlock; |
|
} |
|
|
|
unlock: |
|
mutex_unlock(&master->lock); |
|
return rc ? : num; |
|
} |
|
|
|
static u32 fsi_i2c_functionality(struct i2c_adapter *adap) |
|
{ |
|
return I2C_FUNC_I2C | I2C_FUNC_PROTOCOL_MANGLING | |
|
I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA; |
|
} |
|
|
|
static struct i2c_bus_recovery_info fsi_i2c_bus_recovery_info = { |
|
.recover_bus = i2c_generic_scl_recovery, |
|
.get_scl = fsi_i2c_get_scl, |
|
.set_scl = fsi_i2c_set_scl, |
|
.get_sda = fsi_i2c_get_sda, |
|
.set_sda = fsi_i2c_set_sda, |
|
.prepare_recovery = fsi_i2c_prepare_recovery, |
|
.unprepare_recovery = fsi_i2c_unprepare_recovery, |
|
}; |
|
|
|
static const struct i2c_algorithm fsi_i2c_algorithm = { |
|
.master_xfer = fsi_i2c_xfer, |
|
.functionality = fsi_i2c_functionality, |
|
}; |
|
|
|
static struct device_node *fsi_i2c_find_port_of_node(struct device_node *fsi, |
|
int port) |
|
{ |
|
struct device_node *np; |
|
u32 port_no; |
|
int rc; |
|
|
|
for_each_child_of_node(fsi, np) { |
|
rc = of_property_read_u32(np, "reg", &port_no); |
|
if (!rc && port_no == port) |
|
return np; |
|
} |
|
|
|
return NULL; |
|
} |
|
|
|
static int fsi_i2c_probe(struct device *dev) |
|
{ |
|
struct fsi_i2c_master *i2c; |
|
struct fsi_i2c_port *port; |
|
struct device_node *np; |
|
u32 port_no, ports, stat; |
|
int rc; |
|
|
|
i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); |
|
if (!i2c) |
|
return -ENOMEM; |
|
|
|
mutex_init(&i2c->lock); |
|
i2c->fsi = to_fsi_dev(dev); |
|
INIT_LIST_HEAD(&i2c->ports); |
|
|
|
rc = fsi_i2c_dev_init(i2c); |
|
if (rc) |
|
return rc; |
|
|
|
rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); |
|
if (rc) |
|
return rc; |
|
|
|
ports = FIELD_GET(I2C_STAT_MAX_PORT, stat) + 1; |
|
dev_dbg(dev, "I2C master has %d ports\n", ports); |
|
|
|
for (port_no = 0; port_no < ports; port_no++) { |
|
np = fsi_i2c_find_port_of_node(dev->of_node, port_no); |
|
if (!of_device_is_available(np)) |
|
continue; |
|
|
|
port = kzalloc(sizeof(*port), GFP_KERNEL); |
|
if (!port) { |
|
of_node_put(np); |
|
break; |
|
} |
|
|
|
port->master = i2c; |
|
port->port = port_no; |
|
|
|
port->adapter.owner = THIS_MODULE; |
|
port->adapter.dev.of_node = np; |
|
port->adapter.dev.parent = dev; |
|
port->adapter.algo = &fsi_i2c_algorithm; |
|
port->adapter.bus_recovery_info = &fsi_i2c_bus_recovery_info; |
|
port->adapter.algo_data = port; |
|
|
|
snprintf(port->adapter.name, sizeof(port->adapter.name), |
|
"i2c_bus-%u", port_no); |
|
|
|
rc = i2c_add_adapter(&port->adapter); |
|
if (rc < 0) { |
|
dev_err(dev, "Failed to register adapter: %d\n", rc); |
|
kfree(port); |
|
continue; |
|
} |
|
|
|
list_add(&port->list, &i2c->ports); |
|
} |
|
|
|
dev_set_drvdata(dev, i2c); |
|
|
|
return 0; |
|
} |
|
|
|
static int fsi_i2c_remove(struct device *dev) |
|
{ |
|
struct fsi_i2c_master *i2c = dev_get_drvdata(dev); |
|
struct fsi_i2c_port *port, *tmp; |
|
|
|
list_for_each_entry_safe(port, tmp, &i2c->ports, list) { |
|
list_del(&port->list); |
|
i2c_del_adapter(&port->adapter); |
|
kfree(port); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static const struct fsi_device_id fsi_i2c_ids[] = { |
|
{ FSI_ENGID_I2C, FSI_VERSION_ANY }, |
|
{ } |
|
}; |
|
|
|
static struct fsi_driver fsi_i2c_driver = { |
|
.id_table = fsi_i2c_ids, |
|
.drv = { |
|
.name = "i2c-fsi", |
|
.bus = &fsi_bus_type, |
|
.probe = fsi_i2c_probe, |
|
.remove = fsi_i2c_remove, |
|
}, |
|
}; |
|
|
|
module_fsi_driver(fsi_i2c_driver); |
|
|
|
MODULE_AUTHOR("Eddie James <[email protected]>"); |
|
MODULE_DESCRIPTION("FSI attached I2C master"); |
|
MODULE_LICENSE("GPL");
|
|
|