linux-stable/drivers/gpio/gpio-max730x.c
Linus Torvalds cff2f741b8 Driver core updates for 3.8-rc1
Here's the large driver core updates for 3.8-rc1.
 
 The biggest thing here is the various __dev* marking removals.  This is
 going to be a pain for the merge with different subsystem trees, I know,
 but all of the patches included here have been ACKed by their various
 subsystem maintainers, as they wanted them to go through here.
 
 If this is too much of a pain, I can pull all of them out of this tree
 and just send you one with the other fixes/updates and then, after
 3.8-rc1 is out, do the rest of the removals to ensure we catch them all,
 it's up to you.  The merges should all be trivial, and Stephen has been
 doing them all in linux-next for a few weeks now quite easily.
 
 Other than the __dev* marking removals, there's nothing major here, some
 firmware loading updates and other minor things in the driver core.
 
 All of these have (much to Stephen's annoyance), been in linux-next for
 a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg Kroah-Hartman:
 "Here's the large driver core updates for 3.8-rc1.

  The biggest thing here is the various __dev* marking removals.  This
  is going to be a pain for the merge with different subsystem trees, I
  know, but all of the patches included here have been ACKed by their
  various subsystem maintainers, as they wanted them to go through here.

  If this is too much of a pain, I can pull all of them out of this tree
  and just send you one with the other fixes/updates and then, after
  3.8-rc1 is out, do the rest of the removals to ensure we catch them
  all, it's up to you.  The merges should all be trivial, and Stephen
  has been doing them all in linux-next for a few weeks now quite
  easily.

  Other than the __dev* marking removals, there's nothing major here,
  some firmware loading updates and other minor things in the driver
  core.

  All of these have (much to Stephen's annoyance), been in linux-next
  for a while.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

Fixed up trivial conflicts in drivers/gpio/gpio-{em,stmpe}.c due to gpio
update.

* tag 'driver-core-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (93 commits)
  modpost.c: Stop checking __dev* section mismatches
  init.h: Remove __dev* sections from the kernel
  acpi: remove use of __devinit
  PCI: Remove __dev* markings
  PCI: Always build setup-bus when PCI is enabled
  PCI: Move pci_uevent into pci-driver.c
  PCI: Remove CONFIG_HOTPLUG ifdefs
  unicore32/PCI: Remove CONFIG_HOTPLUG ifdefs
  sh/PCI: Remove CONFIG_HOTPLUG ifdefs
  powerpc/PCI: Remove CONFIG_HOTPLUG ifdefs
  mips/PCI: Remove CONFIG_HOTPLUG ifdefs
  microblaze/PCI: Remove CONFIG_HOTPLUG ifdefs
  dma: remove use of __devinit
  dma: remove use of __devexit_p
  firewire: remove use of __devinitdata
  firewire: remove use of __devinit
  leds: remove use of __devexit
  leds: remove use of __devinit
  leds: remove use of __devexit_p
  mmc: remove use of __devexit
  ...
2012-12-11 13:13:55 -08:00

255 lines
6 KiB
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>
#include <linux/slab.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, pin_config;
int ret;
/* First 4 pins are unused in the controller */
offset += 4;
offset_bits = (offset & 3) << 1;
config = &ts->port_config[offset >> 2];
if (ts->input_pullup_active & BIT(offset))
pin_config = PIN_CONFIG_IN_PULLUP;
else
pin_config = PIN_CONFIG_IN_WO_PULLUP;
mutex_lock(&ts->lock);
*config = (*config & ~(PIN_CONFIG_MASK << offset_bits))
| (pin_config << 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 __max730x_probe(struct max7301 *ts)
{
struct device *dev = ts->dev;
struct max7301_platform_data *pdata;
int i, ret;
pdata = dev->platform_data;
mutex_init(&ts->lock);
dev_set_drvdata(dev, ts);
/* Power up the chip and disable IRQ output */
ts->write(dev, 0x04, 0x01);
if (pdata) {
ts->input_pullup_active = pdata->input_pullup_active;
ts->chip.base = pdata->base;
} else {
ts->chip.base = -1;
}
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.ngpio = PIN_NUMBER;
ts->chip.can_sleep = 1;
ts->chip.dev = dev;
ts->chip.owner = THIS_MODULE;
/*
* initialize pullups according to platform data and cache the
* register values for later use.
*/
for (i = 1; i < 8; i++) {
int j;
/*
* initialize port_config with "0xAA", which means
* input with internal pullup disabled. This is needed
* to avoid writing zeros (in the inner for loop),
* which is not allowed according to the datasheet.
*/
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 __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);
MODULE_AUTHOR("Juergen Beisert, Wolfram Sang");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("MAX730x GPIO-Expanders, generic parts");