gpio: add driver for MAX7300 I2C GPIO extender
Add the MAX7300-I2C variant of the MAX7301-SPI version. Both chips share the same core logic, so the generic part of the in-kernel SPI-driver is refactored into a generic part. The I2C and SPI specific funtions are then wrapped into seperate drivers picking up the generic part. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Cc: Juergen Beisert <j.beisert@pengutronix.de> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Jean Delvare <khali@linux-fr.org> Cc: Anton Vorontsov <avorontsov@ru.mvista.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Родитель
5a98c04d78
Коммит
e952805d2d
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@ -65,6 +65,9 @@ config GPIO_SYSFS
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# put expanders in the right section, in alphabetical order
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config GPIO_MAX730X
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tristate
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comment "Memory mapped GPIO expanders:"
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config GPIO_PL061
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@ -87,6 +90,13 @@ config GPIO_VR41XX
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comment "I2C GPIO expanders:"
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config GPIO_MAX7300
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tristate "Maxim MAX7300 GPIO expander"
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depends on I2C
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select GPIO_MAX730X
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help
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GPIO driver for Maxim MAX7301 I2C-based GPIO expander.
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config GPIO_MAX732X
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tristate "MAX7319, MAX7320-7327 I2C Port Expanders"
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depends on I2C
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@ -226,8 +236,9 @@ comment "SPI GPIO expanders:"
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config GPIO_MAX7301
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tristate "Maxim MAX7301 GPIO expander"
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depends on SPI_MASTER
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select GPIO_MAX730X
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help
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gpio driver for Maxim MAX7301 SPI GPIO expander.
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GPIO driver for Maxim MAX7301 SPI-based GPIO expander.
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config GPIO_MCP23S08
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tristate "Microchip MCP23S08 I/O expander"
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@ -7,6 +7,8 @@ obj-$(CONFIG_GPIOLIB) += gpiolib.o
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obj-$(CONFIG_GPIO_ADP5520) += adp5520-gpio.o
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obj-$(CONFIG_GPIO_ADP5588) += adp5588-gpio.o
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obj-$(CONFIG_GPIO_LANGWELL) += langwell_gpio.o
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obj-$(CONFIG_GPIO_MAX730X) += max730x.o
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obj-$(CONFIG_GPIO_MAX7300) += max7300.o
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obj-$(CONFIG_GPIO_MAX7301) += max7301.o
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obj-$(CONFIG_GPIO_MAX732X) += max732x.o
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obj-$(CONFIG_GPIO_MC33880) += mc33880.o
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@ -0,0 +1,94 @@
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/*
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* drivers/gpio/max7300.c
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*
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* Copyright (C) 2009 Wolfram Sang, Pengutronix
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* Check max730x.c for further details.
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/platform_device.h>
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#include <linux/mutex.h>
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#include <linux/i2c.h>
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#include <linux/spi/max7301.h>
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static int max7300_i2c_write(struct device *dev, unsigned int reg,
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unsigned int val)
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{
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struct i2c_client *client = to_i2c_client(dev);
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return i2c_smbus_write_byte_data(client, reg, val);
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}
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static int max7300_i2c_read(struct device *dev, unsigned int reg)
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{
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struct i2c_client *client = to_i2c_client(dev);
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return i2c_smbus_read_byte_data(client, reg);
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}
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static int __devinit max7300_probe(struct i2c_client *client,
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const struct i2c_device_id *id)
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{
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struct max7301 *ts;
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int ret;
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if (!i2c_check_functionality(client->adapter,
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I2C_FUNC_SMBUS_BYTE_DATA))
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return -EIO;
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ts = kzalloc(sizeof(struct max7301), GFP_KERNEL);
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if (!ts)
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return -ENOMEM;
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ts->read = max7300_i2c_read;
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ts->write = max7300_i2c_write;
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ts->dev = &client->dev;
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ret = __max730x_probe(ts);
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if (ret)
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kfree(ts);
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return ret;
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}
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static int __devexit max7300_remove(struct i2c_client *client)
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{
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return __max730x_remove(&client->dev);
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}
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static const struct i2c_device_id max7300_id[] = {
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{ "max7300", 0 },
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{ }
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};
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MODULE_DEVICE_TABLE(i2c, max7300_id);
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static struct i2c_driver max7300_driver = {
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.driver = {
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.name = "max7300",
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.owner = THIS_MODULE,
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},
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.probe = max7300_probe,
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.remove = __devexit_p(max7300_remove),
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.id_table = max7300_id,
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};
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static int __init max7300_init(void)
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{
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return i2c_add_driver(&max7300_driver);
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}
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subsys_initcall(max7300_init);
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static void __exit max7300_exit(void)
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{
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i2c_del_driver(&max7300_driver);
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}
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module_exit(max7300_exit);
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MODULE_AUTHOR("Wolfram Sang");
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MODULE_LICENSE("GPL v2");
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MODULE_DESCRIPTION("MAX7300 GPIO-Expander");
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@ -1,98 +1,41 @@
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/**
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/*
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* drivers/gpio/max7301.c
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*
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* Copyright (C) 2006 Juergen Beisert, Pengutronix
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* Copyright (C) 2008 Guennadi Liakhovetski, Pengutronix
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* Copyright (C) 2009 Wolfram Sang, Pengutronix
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* The Maxim's MAX7301 device is an SPI driven GPIO expander. There are
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* 28 GPIOs. 8 of them can trigger an interrupt. See datasheet for more
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* details
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* Note:
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* - DIN must be stable at the rising edge of clock.
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* - when writing:
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* - always clock in 16 clocks at once
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* - at DIN: D15 first, D0 last
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* - D0..D7 = databyte, D8..D14 = commandbyte
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* - D15 = low -> write command
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* - when reading
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* - always clock in 16 clocks at once
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* - at DIN: D15 first, D0 last
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* - D0..D7 = dummy, D8..D14 = register address
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* - D15 = high -> read command
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* - raise CS and assert it again
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* - always clock in 16 clocks at once
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* - at DOUT: D15 first, D0 last
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* - D0..D7 contains the data from the first cycle
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*
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* The driver exports a standard gpiochip interface
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* Check max730x.c for further details.
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/platform_device.h>
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#include <linux/mutex.h>
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#include <linux/spi/spi.h>
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#include <linux/spi/max7301.h>
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#include <linux/gpio.h>
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#define DRIVER_NAME "max7301"
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/*
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* Pin configurations, see MAX7301 datasheet page 6
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*/
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#define PIN_CONFIG_MASK 0x03
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#define PIN_CONFIG_IN_PULLUP 0x03
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#define PIN_CONFIG_IN_WO_PULLUP 0x02
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#define PIN_CONFIG_OUT 0x01
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#define PIN_NUMBER 28
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/*
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* Some registers must be read back to modify.
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* To save time we cache them here in memory
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*/
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struct max7301 {
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struct mutex lock;
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u8 port_config[8]; /* field 0 is unused */
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u32 out_level; /* cached output levels */
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struct gpio_chip chip;
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struct spi_device *spi;
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};
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/**
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* max7301_write - Write a new register content
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* @spi: The SPI device
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* @reg: Register offset
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* @val: Value to write
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*
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* A write to the MAX7301 means one message with one transfer
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*
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* Returns 0 if successful or a negative value on error
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*/
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static int max7301_write(struct spi_device *spi, unsigned int reg, unsigned int val)
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/* A write to the MAX7301 means one message with one transfer */
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static int max7301_spi_write(struct device *dev, unsigned int reg,
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unsigned int val)
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{
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struct spi_device *spi = to_spi_device(dev);
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u16 word = ((reg & 0x7F) << 8) | (val & 0xFF);
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return spi_write(spi, (const u8 *)&word, sizeof(word));
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}
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/**
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* max7301_read - Read back register content
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* @spi: The SPI device
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* @reg: Register offset
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*
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* A read from the MAX7301 means two transfers; here, one message each
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*
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* Returns positive 8 bit value from device if successful or a
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* negative value on error
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*/
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static int max7301_read(struct spi_device *spi, unsigned int reg)
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/* A read from the MAX7301 means two transfers; here, one message each */
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static int max7301_spi_read(struct device *dev, unsigned int reg)
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{
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int ret;
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u16 word;
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struct spi_device *spi = to_spi_device(dev);
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word = 0x8000 | (reg << 8);
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ret = spi_write(spi, (const u8 *)&word, sizeof(word));
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@ -108,125 +51,13 @@ static int max7301_read(struct spi_device *spi, unsigned int reg)
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return word & 0xff;
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}
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static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
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{
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struct max7301 *ts = container_of(chip, struct max7301, chip);
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u8 *config;
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int ret;
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/* First 4 pins are unused in the controller */
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offset += 4;
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config = &ts->port_config[offset >> 2];
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mutex_lock(&ts->lock);
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/* Standard GPIO API doesn't support pull-ups, has to be extended.
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* Hard-coding no pollup for now. */
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*config = (*config & ~(3 << (offset & 3))) | (1 << (offset & 3));
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ret = max7301_write(ts->spi, 0x08 + (offset >> 2), *config);
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mutex_unlock(&ts->lock);
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return ret;
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}
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static int __max7301_set(struct max7301 *ts, unsigned offset, int value)
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{
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if (value) {
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ts->out_level |= 1 << offset;
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return max7301_write(ts->spi, 0x20 + offset, 0x01);
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} else {
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ts->out_level &= ~(1 << offset);
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return max7301_write(ts->spi, 0x20 + offset, 0x00);
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}
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}
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static int max7301_direction_output(struct gpio_chip *chip, unsigned offset,
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int value)
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{
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struct max7301 *ts = container_of(chip, struct max7301, chip);
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u8 *config;
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int ret;
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/* First 4 pins are unused in the controller */
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offset += 4;
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config = &ts->port_config[offset >> 2];
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mutex_lock(&ts->lock);
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*config = (*config & ~(3 << (offset & 3))) | (1 << (offset & 3));
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ret = __max7301_set(ts, offset, value);
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if (!ret)
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ret = max7301_write(ts->spi, 0x08 + (offset >> 2), *config);
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mutex_unlock(&ts->lock);
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return ret;
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}
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static int max7301_get(struct gpio_chip *chip, unsigned offset)
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{
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struct max7301 *ts = container_of(chip, struct max7301, chip);
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int config, level = -EINVAL;
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/* First 4 pins are unused in the controller */
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offset += 4;
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mutex_lock(&ts->lock);
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config = (ts->port_config[offset >> 2] >> ((offset & 3) * 2)) & 3;
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switch (config) {
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case 1:
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/* Output: return cached level */
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level = !!(ts->out_level & (1 << offset));
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break;
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case 2:
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case 3:
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/* Input: read out */
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level = max7301_read(ts->spi, 0x20 + offset) & 0x01;
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}
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mutex_unlock(&ts->lock);
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return level;
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}
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static void max7301_set(struct gpio_chip *chip, unsigned offset, int value)
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{
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struct max7301 *ts = container_of(chip, struct max7301, chip);
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/* First 4 pins are unused in the controller */
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offset += 4;
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mutex_lock(&ts->lock);
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__max7301_set(ts, offset, value);
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mutex_unlock(&ts->lock);
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}
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static int __devinit max7301_probe(struct spi_device *spi)
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{
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struct max7301 *ts;
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struct max7301_platform_data *pdata;
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int i, ret;
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int ret;
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pdata = spi->dev.platform_data;
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if (!pdata || !pdata->base) {
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dev_dbg(&spi->dev, "incorrect or missing platform data\n");
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return -EINVAL;
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}
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/*
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* bits_per_word cannot be configured in platform data
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*/
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/* bits_per_word cannot be configured in platform data */
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spi->bits_per_word = 16;
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ret = spi_setup(spi);
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if (ret < 0)
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return ret;
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@ -235,90 +66,35 @@ static int __devinit max7301_probe(struct spi_device *spi)
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if (!ts)
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return -ENOMEM;
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mutex_init(&ts->lock);
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ts->read = max7301_spi_read;
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ts->write = max7301_spi_write;
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ts->dev = &spi->dev;
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dev_set_drvdata(&spi->dev, ts);
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/* Power up the chip and disable IRQ output */
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max7301_write(spi, 0x04, 0x01);
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ts->spi = spi;
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ts->chip.label = DRIVER_NAME,
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ts->chip.direction_input = max7301_direction_input;
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ts->chip.get = max7301_get;
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ts->chip.direction_output = max7301_direction_output;
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ts->chip.set = max7301_set;
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ts->chip.base = pdata->base;
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ts->chip.ngpio = PIN_NUMBER;
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ts->chip.can_sleep = 1;
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ts->chip.dev = &spi->dev;
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ts->chip.owner = THIS_MODULE;
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/*
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* tristate all pins in hardware and cache the
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* register values for later use.
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*/
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for (i = 1; i < 8; i++) {
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int j;
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/* 0xAA means input with internal pullup disabled */
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max7301_write(spi, 0x08 + i, 0xAA);
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ts->port_config[i] = 0xAA;
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for (j = 0; j < 4; j++) {
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int offset = (i - 1) * 4 + j;
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ret = max7301_direction_input(&ts->chip, offset);
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if (ret)
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goto exit_destroy;
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}
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}
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ret = gpiochip_add(&ts->chip);
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ret = __max730x_probe(ts);
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if (ret)
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goto exit_destroy;
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return ret;
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exit_destroy:
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dev_set_drvdata(&spi->dev, NULL);
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mutex_destroy(&ts->lock);
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kfree(ts);
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kfree(ts);
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return ret;
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}
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static int __devexit max7301_remove(struct spi_device *spi)
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{
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struct max7301 *ts;
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int ret;
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ts = dev_get_drvdata(&spi->dev);
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if (ts == NULL)
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return -ENODEV;
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dev_set_drvdata(&spi->dev, NULL);
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/* Power down the chip and disable IRQ output */
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max7301_write(spi, 0x04, 0x00);
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ret = gpiochip_remove(&ts->chip);
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if (!ret) {
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mutex_destroy(&ts->lock);
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kfree(ts);
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} else
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dev_err(&spi->dev, "Failed to remove the GPIO controller: %d\n",
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ret);
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return ret;
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return __max730x_remove(&spi->dev);
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}
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static const struct spi_device_id max7301_id[] = {
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{ "max7301", 0 },
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{ }
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};
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MODULE_DEVICE_TABLE(spi, max7301_id);
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static struct spi_driver max7301_driver = {
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.driver = {
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.name = DRIVER_NAME,
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.owner = THIS_MODULE,
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.name = "max7301",
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.owner = THIS_MODULE,
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},
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.probe = max7301_probe,
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.remove = __devexit_p(max7301_remove),
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.probe = max7301_probe,
|
||||
.remove = __devexit_p(max7301_remove),
|
||||
.id_table = max7301_id,
|
||||
};
|
||||
|
||||
static int __init max7301_init(void)
|
||||
|
@ -336,7 +112,6 @@ static void __exit max7301_exit(void)
|
|||
}
|
||||
module_exit(max7301_exit);
|
||||
|
||||
MODULE_AUTHOR("Juergen Beisert");
|
||||
MODULE_AUTHOR("Juergen Beisert, Wolfram Sang");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
MODULE_DESCRIPTION("MAX7301 SPI based GPIO-Expander");
|
||||
MODULE_ALIAS("spi:" DRIVER_NAME);
|
||||
MODULE_DESCRIPTION("MAX7301 GPIO-Expander");
|
||||
|
|
|
@ -0,0 +1,244 @@
|
|||
/**
|
||||
* drivers/gpio/max7301.c
|
||||
*
|
||||
* Copyright (C) 2006 Juergen Beisert, Pengutronix
|
||||
* Copyright (C) 2008 Guennadi Liakhovetski, Pengutronix
|
||||
* Copyright (C) 2009 Wolfram Sang, Pengutronix
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License version 2 as
|
||||
* published by the Free Software Foundation.
|
||||
*
|
||||
* The Maxim MAX7300/1 device is an I2C/SPI driven GPIO expander. There are
|
||||
* 28 GPIOs. 8 of them can trigger an interrupt. See datasheet for more
|
||||
* details
|
||||
* Note:
|
||||
* - DIN must be stable at the rising edge of clock.
|
||||
* - when writing:
|
||||
* - always clock in 16 clocks at once
|
||||
* - at DIN: D15 first, D0 last
|
||||
* - D0..D7 = databyte, D8..D14 = commandbyte
|
||||
* - D15 = low -> write command
|
||||
* - when reading
|
||||
* - always clock in 16 clocks at once
|
||||
* - at DIN: D15 first, D0 last
|
||||
* - D0..D7 = dummy, D8..D14 = register address
|
||||
* - D15 = high -> read command
|
||||
* - raise CS and assert it again
|
||||
* - always clock in 16 clocks at once
|
||||
* - at DOUT: D15 first, D0 last
|
||||
* - D0..D7 contains the data from the first cycle
|
||||
*
|
||||
* The driver exports a standard gpiochip interface
|
||||
*/
|
||||
|
||||
#include <linux/module.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/spi/max7301.h>
|
||||
#include <linux/gpio.h>
|
||||
|
||||
/*
|
||||
* Pin configurations, see MAX7301 datasheet page 6
|
||||
*/
|
||||
#define PIN_CONFIG_MASK 0x03
|
||||
#define PIN_CONFIG_IN_PULLUP 0x03
|
||||
#define PIN_CONFIG_IN_WO_PULLUP 0x02
|
||||
#define PIN_CONFIG_OUT 0x01
|
||||
|
||||
#define PIN_NUMBER 28
|
||||
|
||||
static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
|
||||
{
|
||||
struct max7301 *ts = container_of(chip, struct max7301, chip);
|
||||
u8 *config;
|
||||
u8 offset_bits;
|
||||
int ret;
|
||||
|
||||
/* First 4 pins are unused in the controller */
|
||||
offset += 4;
|
||||
offset_bits = (offset & 3) << 1;
|
||||
|
||||
config = &ts->port_config[offset >> 2];
|
||||
|
||||
mutex_lock(&ts->lock);
|
||||
|
||||
/* Standard GPIO API doesn't support pull-ups, has to be extended.
|
||||
* Hard-coding no pollup for now. */
|
||||
*config = (*config & ~(PIN_CONFIG_MASK << offset_bits))
|
||||
| (PIN_CONFIG_IN_WO_PULLUP << offset_bits);
|
||||
|
||||
ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);
|
||||
|
||||
mutex_unlock(&ts->lock);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int __max7301_set(struct max7301 *ts, unsigned offset, int value)
|
||||
{
|
||||
if (value) {
|
||||
ts->out_level |= 1 << offset;
|
||||
return ts->write(ts->dev, 0x20 + offset, 0x01);
|
||||
} else {
|
||||
ts->out_level &= ~(1 << offset);
|
||||
return ts->write(ts->dev, 0x20 + offset, 0x00);
|
||||
}
|
||||
}
|
||||
|
||||
static int max7301_direction_output(struct gpio_chip *chip, unsigned offset,
|
||||
int value)
|
||||
{
|
||||
struct max7301 *ts = container_of(chip, struct max7301, chip);
|
||||
u8 *config;
|
||||
u8 offset_bits;
|
||||
int ret;
|
||||
|
||||
/* First 4 pins are unused in the controller */
|
||||
offset += 4;
|
||||
offset_bits = (offset & 3) << 1;
|
||||
|
||||
config = &ts->port_config[offset >> 2];
|
||||
|
||||
mutex_lock(&ts->lock);
|
||||
|
||||
*config = (*config & ~(PIN_CONFIG_MASK << offset_bits))
|
||||
| (PIN_CONFIG_OUT << offset_bits);
|
||||
|
||||
ret = __max7301_set(ts, offset, value);
|
||||
|
||||
if (!ret)
|
||||
ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);
|
||||
|
||||
mutex_unlock(&ts->lock);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int max7301_get(struct gpio_chip *chip, unsigned offset)
|
||||
{
|
||||
struct max7301 *ts = container_of(chip, struct max7301, chip);
|
||||
int config, level = -EINVAL;
|
||||
|
||||
/* First 4 pins are unused in the controller */
|
||||
offset += 4;
|
||||
|
||||
mutex_lock(&ts->lock);
|
||||
|
||||
config = (ts->port_config[offset >> 2] >> ((offset & 3) << 1))
|
||||
& PIN_CONFIG_MASK;
|
||||
|
||||
switch (config) {
|
||||
case PIN_CONFIG_OUT:
|
||||
/* Output: return cached level */
|
||||
level = !!(ts->out_level & (1 << offset));
|
||||
break;
|
||||
case PIN_CONFIG_IN_WO_PULLUP:
|
||||
case PIN_CONFIG_IN_PULLUP:
|
||||
/* Input: read out */
|
||||
level = ts->read(ts->dev, 0x20 + offset) & 0x01;
|
||||
}
|
||||
mutex_unlock(&ts->lock);
|
||||
|
||||
return level;
|
||||
}
|
||||
|
||||
static void max7301_set(struct gpio_chip *chip, unsigned offset, int value)
|
||||
{
|
||||
struct max7301 *ts = container_of(chip, struct max7301, chip);
|
||||
|
||||
/* First 4 pins are unused in the controller */
|
||||
offset += 4;
|
||||
|
||||
mutex_lock(&ts->lock);
|
||||
|
||||
__max7301_set(ts, offset, value);
|
||||
|
||||
mutex_unlock(&ts->lock);
|
||||
}
|
||||
|
||||
int __devinit __max730x_probe(struct max7301 *ts)
|
||||
{
|
||||
struct device *dev = ts->dev;
|
||||
struct max7301_platform_data *pdata;
|
||||
int i, ret;
|
||||
|
||||
pdata = dev->platform_data;
|
||||
if (!pdata || !pdata->base) {
|
||||
dev_err(dev, "incorrect or missing platform data\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
mutex_init(&ts->lock);
|
||||
dev_set_drvdata(dev, ts);
|
||||
|
||||
/* Power up the chip and disable IRQ output */
|
||||
ts->write(dev, 0x04, 0x01);
|
||||
|
||||
ts->chip.label = dev->driver->name;
|
||||
|
||||
ts->chip.direction_input = max7301_direction_input;
|
||||
ts->chip.get = max7301_get;
|
||||
ts->chip.direction_output = max7301_direction_output;
|
||||
ts->chip.set = max7301_set;
|
||||
|
||||
ts->chip.base = pdata->base;
|
||||
ts->chip.ngpio = PIN_NUMBER;
|
||||
ts->chip.can_sleep = 1;
|
||||
ts->chip.dev = dev;
|
||||
ts->chip.owner = THIS_MODULE;
|
||||
|
||||
/*
|
||||
* tristate all pins in hardware and cache the
|
||||
* register values for later use.
|
||||
*/
|
||||
for (i = 1; i < 8; i++) {
|
||||
int j;
|
||||
/* 0xAA means input with internal pullup disabled */
|
||||
ts->write(dev, 0x08 + i, 0xAA);
|
||||
ts->port_config[i] = 0xAA;
|
||||
for (j = 0; j < 4; j++) {
|
||||
int offset = (i - 1) * 4 + j;
|
||||
ret = max7301_direction_input(&ts->chip, offset);
|
||||
if (ret)
|
||||
goto exit_destroy;
|
||||
}
|
||||
}
|
||||
|
||||
ret = gpiochip_add(&ts->chip);
|
||||
if (ret)
|
||||
goto exit_destroy;
|
||||
|
||||
return ret;
|
||||
|
||||
exit_destroy:
|
||||
dev_set_drvdata(dev, NULL);
|
||||
mutex_destroy(&ts->lock);
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(__max730x_probe);
|
||||
|
||||
int __devexit __max730x_remove(struct device *dev)
|
||||
{
|
||||
struct max7301 *ts = dev_get_drvdata(dev);
|
||||
int ret;
|
||||
|
||||
if (ts == NULL)
|
||||
return -ENODEV;
|
||||
|
||||
dev_set_drvdata(dev, NULL);
|
||||
|
||||
/* Power down the chip and disable IRQ output */
|
||||
ts->write(dev, 0x04, 0x00);
|
||||
|
||||
ret = gpiochip_remove(&ts->chip);
|
||||
if (!ret) {
|
||||
mutex_destroy(&ts->lock);
|
||||
kfree(ts);
|
||||
} else
|
||||
dev_err(dev, "Failed to remove GPIO controller: %d\n", ret);
|
||||
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(__max730x_remove);
|
|
@ -1,9 +1,27 @@
|
|||
#ifndef LINUX_SPI_MAX7301_H
|
||||
#define LINUX_SPI_MAX7301_H
|
||||
|
||||
#include <linux/gpio.h>
|
||||
|
||||
/*
|
||||
* Some registers must be read back to modify.
|
||||
* To save time we cache them here in memory
|
||||
*/
|
||||
struct max7301 {
|
||||
struct mutex lock;
|
||||
u8 port_config[8]; /* field 0 is unused */
|
||||
u32 out_level; /* cached output levels */
|
||||
struct gpio_chip chip;
|
||||
struct device *dev;
|
||||
int (*write)(struct device *dev, unsigned int reg, unsigned int val);
|
||||
int (*read)(struct device *dev, unsigned int reg);
|
||||
};
|
||||
|
||||
struct max7301_platform_data {
|
||||
/* number assigned to the first GPIO */
|
||||
unsigned base;
|
||||
};
|
||||
|
||||
extern int __max730x_remove(struct device *dev);
|
||||
extern int __max730x_probe(struct max7301 *ts);
|
||||
#endif
|
||||
|
|
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