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370 lines
8.4 KiB
370 lines
8.4 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* i2c Support for Atmel's AT91 Two-Wire Interface (TWI) |
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* |
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* Copyright (C) 2011 Weinmann Medical GmbH |
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* Author: Nikolaus Voss <[email protected]> |
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* |
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* Evolved from original work by: |
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* Copyright (C) 2004 Rick Bronson |
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* Converted to 2.6 by Andrew Victor <[email protected]> |
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* |
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* Borrowed heavily from original work by: |
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* Copyright (C) 2000 Philip Edelbrock <[email protected]> |
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*/ |
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#include <linux/clk.h> |
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#include <linux/err.h> |
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#include <linux/i2c.h> |
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#include <linux/io.h> |
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#include <linux/module.h> |
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#include <linux/of.h> |
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#include <linux/of_device.h> |
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#include <linux/platform_device.h> |
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#include <linux/pm_runtime.h> |
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#include <linux/pinctrl/consumer.h> |
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#include "i2c-at91.h" |
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unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg) |
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{ |
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return readl_relaxed(dev->base + reg); |
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} |
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void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val) |
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{ |
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writel_relaxed(val, dev->base + reg); |
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} |
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void at91_disable_twi_interrupts(struct at91_twi_dev *dev) |
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{ |
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at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_INT_MASK); |
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} |
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void at91_twi_irq_save(struct at91_twi_dev *dev) |
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{ |
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dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & AT91_TWI_INT_MASK; |
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at91_disable_twi_interrupts(dev); |
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} |
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void at91_twi_irq_restore(struct at91_twi_dev *dev) |
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{ |
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at91_twi_write(dev, AT91_TWI_IER, dev->imr); |
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} |
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void at91_init_twi_bus(struct at91_twi_dev *dev) |
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{ |
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at91_disable_twi_interrupts(dev); |
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at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST); |
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if (dev->slave_detected) |
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at91_init_twi_bus_slave(dev); |
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else |
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at91_init_twi_bus_master(dev); |
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} |
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static struct at91_twi_pdata at91rm9200_config = { |
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.clk_max_div = 5, |
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.clk_offset = 3, |
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.has_unre_flag = true, |
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}; |
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static struct at91_twi_pdata at91sam9261_config = { |
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.clk_max_div = 5, |
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.clk_offset = 4, |
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}; |
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static struct at91_twi_pdata at91sam9260_config = { |
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.clk_max_div = 7, |
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.clk_offset = 4, |
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}; |
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static struct at91_twi_pdata at91sam9g20_config = { |
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.clk_max_div = 7, |
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.clk_offset = 4, |
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}; |
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static struct at91_twi_pdata at91sam9g10_config = { |
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.clk_max_div = 7, |
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.clk_offset = 4, |
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}; |
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static const struct platform_device_id at91_twi_devtypes[] = { |
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{ |
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.name = "i2c-at91rm9200", |
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.driver_data = (unsigned long) &at91rm9200_config, |
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}, { |
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.name = "i2c-at91sam9261", |
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.driver_data = (unsigned long) &at91sam9261_config, |
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}, { |
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.name = "i2c-at91sam9260", |
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.driver_data = (unsigned long) &at91sam9260_config, |
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}, { |
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.name = "i2c-at91sam9g20", |
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.driver_data = (unsigned long) &at91sam9g20_config, |
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}, { |
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.name = "i2c-at91sam9g10", |
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.driver_data = (unsigned long) &at91sam9g10_config, |
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}, { |
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/* sentinel */ |
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} |
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}; |
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#if defined(CONFIG_OF) |
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static struct at91_twi_pdata at91sam9x5_config = { |
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.clk_max_div = 7, |
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.clk_offset = 4, |
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}; |
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static struct at91_twi_pdata sama5d4_config = { |
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.clk_max_div = 7, |
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.clk_offset = 4, |
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.has_hold_field = true, |
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.has_dig_filtr = true, |
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}; |
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static struct at91_twi_pdata sama5d2_config = { |
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.clk_max_div = 7, |
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.clk_offset = 3, |
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.has_unre_flag = true, |
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.has_alt_cmd = true, |
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.has_hold_field = true, |
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.has_dig_filtr = true, |
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.has_adv_dig_filtr = true, |
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.has_ana_filtr = true, |
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.has_clear_cmd = false, /* due to errata, CLEAR cmd is not working */ |
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}; |
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static struct at91_twi_pdata sam9x60_config = { |
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.clk_max_div = 7, |
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.clk_offset = 3, |
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.has_unre_flag = true, |
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.has_alt_cmd = true, |
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.has_hold_field = true, |
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.has_dig_filtr = true, |
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.has_adv_dig_filtr = true, |
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.has_ana_filtr = true, |
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.has_clear_cmd = true, |
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}; |
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static const struct of_device_id atmel_twi_dt_ids[] = { |
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{ |
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.compatible = "atmel,at91rm9200-i2c", |
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.data = &at91rm9200_config, |
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}, { |
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.compatible = "atmel,at91sam9260-i2c", |
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.data = &at91sam9260_config, |
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}, { |
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.compatible = "atmel,at91sam9261-i2c", |
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.data = &at91sam9261_config, |
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}, { |
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.compatible = "atmel,at91sam9g20-i2c", |
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.data = &at91sam9g20_config, |
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}, { |
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.compatible = "atmel,at91sam9g10-i2c", |
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.data = &at91sam9g10_config, |
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}, { |
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.compatible = "atmel,at91sam9x5-i2c", |
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.data = &at91sam9x5_config, |
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}, { |
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.compatible = "atmel,sama5d4-i2c", |
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.data = &sama5d4_config, |
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}, { |
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.compatible = "atmel,sama5d2-i2c", |
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.data = &sama5d2_config, |
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}, { |
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.compatible = "microchip,sam9x60-i2c", |
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.data = &sam9x60_config, |
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}, { |
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/* sentinel */ |
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} |
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}; |
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MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids); |
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#endif |
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static struct at91_twi_pdata *at91_twi_get_driver_data( |
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struct platform_device *pdev) |
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{ |
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if (pdev->dev.of_node) { |
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const struct of_device_id *match; |
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match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node); |
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if (!match) |
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return NULL; |
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return (struct at91_twi_pdata *)match->data; |
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} |
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return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data; |
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} |
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static int at91_twi_probe(struct platform_device *pdev) |
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{ |
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struct at91_twi_dev *dev; |
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struct resource *mem; |
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int rc; |
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u32 phy_addr; |
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dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); |
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if (!dev) |
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return -ENOMEM; |
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dev->dev = &pdev->dev; |
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mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
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if (!mem) |
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return -ENODEV; |
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phy_addr = mem->start; |
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dev->pdata = at91_twi_get_driver_data(pdev); |
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if (!dev->pdata) |
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return -ENODEV; |
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dev->base = devm_ioremap_resource(&pdev->dev, mem); |
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if (IS_ERR(dev->base)) |
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return PTR_ERR(dev->base); |
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dev->irq = platform_get_irq(pdev, 0); |
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if (dev->irq < 0) |
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return dev->irq; |
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platform_set_drvdata(pdev, dev); |
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dev->clk = devm_clk_get(dev->dev, NULL); |
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if (IS_ERR(dev->clk)) { |
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dev_err(dev->dev, "no clock defined\n"); |
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return -ENODEV; |
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} |
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clk_prepare_enable(dev->clk); |
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snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91"); |
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i2c_set_adapdata(&dev->adapter, dev); |
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dev->adapter.owner = THIS_MODULE; |
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dev->adapter.class = I2C_CLASS_DEPRECATED; |
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dev->adapter.dev.parent = dev->dev; |
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dev->adapter.nr = pdev->id; |
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dev->adapter.timeout = AT91_I2C_TIMEOUT; |
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dev->adapter.dev.of_node = pdev->dev.of_node; |
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dev->slave_detected = i2c_detect_slave_mode(&pdev->dev); |
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if (dev->slave_detected) |
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rc = at91_twi_probe_slave(pdev, phy_addr, dev); |
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else |
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rc = at91_twi_probe_master(pdev, phy_addr, dev); |
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if (rc) |
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return rc; |
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at91_init_twi_bus(dev); |
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pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT); |
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pm_runtime_use_autosuspend(dev->dev); |
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pm_runtime_set_active(dev->dev); |
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pm_runtime_enable(dev->dev); |
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rc = i2c_add_numbered_adapter(&dev->adapter); |
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if (rc) { |
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clk_disable_unprepare(dev->clk); |
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pm_runtime_disable(dev->dev); |
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pm_runtime_set_suspended(dev->dev); |
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return rc; |
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} |
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dev_info(dev->dev, "AT91 i2c bus driver (hw version: %#x).\n", |
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at91_twi_read(dev, AT91_TWI_VER)); |
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return 0; |
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} |
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static int at91_twi_remove(struct platform_device *pdev) |
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{ |
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struct at91_twi_dev *dev = platform_get_drvdata(pdev); |
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i2c_del_adapter(&dev->adapter); |
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clk_disable_unprepare(dev->clk); |
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pm_runtime_disable(dev->dev); |
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pm_runtime_set_suspended(dev->dev); |
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return 0; |
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} |
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static int __maybe_unused at91_twi_runtime_suspend(struct device *dev) |
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{ |
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struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); |
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clk_disable_unprepare(twi_dev->clk); |
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pinctrl_pm_select_sleep_state(dev); |
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return 0; |
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} |
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static int __maybe_unused at91_twi_runtime_resume(struct device *dev) |
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{ |
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struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); |
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pinctrl_pm_select_default_state(dev); |
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return clk_prepare_enable(twi_dev->clk); |
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} |
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static int __maybe_unused at91_twi_suspend_noirq(struct device *dev) |
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{ |
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if (!pm_runtime_status_suspended(dev)) |
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at91_twi_runtime_suspend(dev); |
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return 0; |
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} |
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static int __maybe_unused at91_twi_resume_noirq(struct device *dev) |
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{ |
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struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); |
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int ret; |
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if (!pm_runtime_status_suspended(dev)) { |
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ret = at91_twi_runtime_resume(dev); |
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if (ret) |
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return ret; |
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} |
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pm_runtime_mark_last_busy(dev); |
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pm_request_autosuspend(dev); |
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at91_init_twi_bus(twi_dev); |
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return 0; |
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} |
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static const struct dev_pm_ops __maybe_unused at91_twi_pm = { |
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.suspend_noirq = at91_twi_suspend_noirq, |
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.resume_noirq = at91_twi_resume_noirq, |
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.runtime_suspend = at91_twi_runtime_suspend, |
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.runtime_resume = at91_twi_runtime_resume, |
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}; |
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static struct platform_driver at91_twi_driver = { |
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.probe = at91_twi_probe, |
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.remove = at91_twi_remove, |
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.id_table = at91_twi_devtypes, |
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.driver = { |
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.name = "at91_i2c", |
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.of_match_table = of_match_ptr(atmel_twi_dt_ids), |
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.pm = pm_ptr(&at91_twi_pm), |
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}, |
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}; |
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static int __init at91_twi_init(void) |
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{ |
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return platform_driver_register(&at91_twi_driver); |
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} |
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static void __exit at91_twi_exit(void) |
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{ |
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platform_driver_unregister(&at91_twi_driver); |
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} |
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subsys_initcall(at91_twi_init); |
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module_exit(at91_twi_exit); |
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MODULE_AUTHOR("Nikolaus Voss <[email protected]>"); |
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MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91"); |
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MODULE_LICENSE("GPL"); |
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MODULE_ALIAS("platform:at91_i2c");
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