linux/drivers/gpio/gpio-sch.c
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iEYEABECAAYFAlSOD20ACgkQMUfUDdst+ylLPACg2QrW1oHhdTMT9WI8jihlHVRM
 53kAoLeteByQ3iVwWurwwseRPiWa8+MI
 =OVRS
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00

264 lines
6.1 KiB
C

/*
* GPIO interface for Intel Poulsbo SCH
*
* Copyright (c) 2010 CompuLab Ltd
* Author: Denis Turischev <denis@compulab.co.il>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License 2 as published
* by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/errno.h>
#include <linux/acpi.h>
#include <linux/platform_device.h>
#include <linux/pci_ids.h>
#include <linux/gpio.h>
#define GEN 0x00
#define GIO 0x04
#define GLV 0x08
struct sch_gpio {
struct gpio_chip chip;
spinlock_t lock;
unsigned short iobase;
unsigned short core_base;
unsigned short resume_base;
};
#define to_sch_gpio(c) container_of(c, struct sch_gpio, chip)
static unsigned sch_gpio_offset(struct sch_gpio *sch, unsigned gpio,
unsigned reg)
{
unsigned base = 0;
if (gpio >= sch->resume_base) {
gpio -= sch->resume_base;
base += 0x20;
}
return base + reg + gpio / 8;
}
static unsigned sch_gpio_bit(struct sch_gpio *sch, unsigned gpio)
{
if (gpio >= sch->resume_base)
gpio -= sch->resume_base;
return gpio % 8;
}
static void sch_gpio_enable(struct sch_gpio *sch, unsigned gpio)
{
unsigned short offset, bit;
u8 enable;
spin_lock(&sch->lock);
offset = sch_gpio_offset(sch, gpio, GEN);
bit = sch_gpio_bit(sch, gpio);
enable = inb(sch->iobase + offset);
if (!(enable & (1 << bit)))
outb(enable | (1 << bit), sch->iobase + offset);
spin_unlock(&sch->lock);
}
static int sch_gpio_direction_in(struct gpio_chip *gc, unsigned gpio_num)
{
struct sch_gpio *sch = to_sch_gpio(gc);
u8 curr_dirs;
unsigned short offset, bit;
spin_lock(&sch->lock);
offset = sch_gpio_offset(sch, gpio_num, GIO);
bit = sch_gpio_bit(sch, gpio_num);
curr_dirs = inb(sch->iobase + offset);
if (!(curr_dirs & (1 << bit)))
outb(curr_dirs | (1 << bit), sch->iobase + offset);
spin_unlock(&sch->lock);
return 0;
}
static int sch_gpio_get(struct gpio_chip *gc, unsigned gpio_num)
{
struct sch_gpio *sch = to_sch_gpio(gc);
int res;
unsigned short offset, bit;
offset = sch_gpio_offset(sch, gpio_num, GLV);
bit = sch_gpio_bit(sch, gpio_num);
res = !!(inb(sch->iobase + offset) & (1 << bit));
return res;
}
static void sch_gpio_set(struct gpio_chip *gc, unsigned gpio_num, int val)
{
struct sch_gpio *sch = to_sch_gpio(gc);
u8 curr_vals;
unsigned short offset, bit;
spin_lock(&sch->lock);
offset = sch_gpio_offset(sch, gpio_num, GLV);
bit = sch_gpio_bit(sch, gpio_num);
curr_vals = inb(sch->iobase + offset);
if (val)
outb(curr_vals | (1 << bit), sch->iobase + offset);
else
outb((curr_vals & ~(1 << bit)), sch->iobase + offset);
spin_unlock(&sch->lock);
}
static int sch_gpio_direction_out(struct gpio_chip *gc, unsigned gpio_num,
int val)
{
struct sch_gpio *sch = to_sch_gpio(gc);
u8 curr_dirs;
unsigned short offset, bit;
spin_lock(&sch->lock);
offset = sch_gpio_offset(sch, gpio_num, GIO);
bit = sch_gpio_bit(sch, gpio_num);
curr_dirs = inb(sch->iobase + offset);
if (curr_dirs & (1 << bit))
outb(curr_dirs & ~(1 << bit), sch->iobase + offset);
spin_unlock(&sch->lock);
/*
* according to the datasheet, writing to the level register has no
* effect when GPIO is programmed as input.
* Actually the the level register is read-only when configured as input.
* Thus presetting the output level before switching to output is _NOT_ possible.
* Hence we set the level after configuring the GPIO as output.
* But we cannot prevent a short low pulse if direction is set to high
* and an external pull-up is connected.
*/
sch_gpio_set(gc, gpio_num, val);
return 0;
}
static struct gpio_chip sch_gpio_chip = {
.label = "sch_gpio",
.owner = THIS_MODULE,
.direction_input = sch_gpio_direction_in,
.get = sch_gpio_get,
.direction_output = sch_gpio_direction_out,
.set = sch_gpio_set,
};
static int sch_gpio_probe(struct platform_device *pdev)
{
struct sch_gpio *sch;
struct resource *res;
sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL);
if (!sch)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (!res)
return -EBUSY;
if (!devm_request_region(&pdev->dev, res->start, resource_size(res),
pdev->name))
return -EBUSY;
spin_lock_init(&sch->lock);
sch->iobase = res->start;
sch->chip = sch_gpio_chip;
sch->chip.label = dev_name(&pdev->dev);
sch->chip.dev = &pdev->dev;
switch (pdev->id) {
case PCI_DEVICE_ID_INTEL_SCH_LPC:
sch->core_base = 0;
sch->resume_base = 10;
sch->chip.ngpio = 14;
/*
* GPIO[6:0] enabled by default
* GPIO7 is configured by the CMC as SLPIOVR
* Enable GPIO[9:8] core powered gpios explicitly
*/
sch_gpio_enable(sch, 8);
sch_gpio_enable(sch, 9);
/*
* SUS_GPIO[2:0] enabled by default
* Enable SUS_GPIO3 resume powered gpio explicitly
*/
sch_gpio_enable(sch, 13);
break;
case PCI_DEVICE_ID_INTEL_ITC_LPC:
sch->core_base = 0;
sch->resume_base = 5;
sch->chip.ngpio = 14;
break;
case PCI_DEVICE_ID_INTEL_CENTERTON_ILB:
sch->core_base = 0;
sch->resume_base = 21;
sch->chip.ngpio = 30;
break;
default:
return -ENODEV;
}
platform_set_drvdata(pdev, sch);
return gpiochip_add(&sch->chip);
}
static int sch_gpio_remove(struct platform_device *pdev)
{
struct sch_gpio *sch = platform_get_drvdata(pdev);
gpiochip_remove(&sch->chip);
return 0;
}
static struct platform_driver sch_gpio_driver = {
.driver = {
.name = "sch_gpio",
},
.probe = sch_gpio_probe,
.remove = sch_gpio_remove,
};
module_platform_driver(sch_gpio_driver);
MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:sch_gpio");