diff options
author | Andres Salomon <dilinger@collabora.co.uk> | 2009-12-14 18:00:32 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-12-15 08:53:27 -0800 |
commit | 5f0a96b044d8edaee20f4a32ef6c393599ca55f8 (patch) | |
tree | a46994e95854d1771ea6829826793f8bceb39751 /drivers | |
parent | 1f2f38d89d1eced2079189cd880eeacee378370a (diff) |
cs5535-gpio: add AMD CS5535/CS5536 GPIO driver support
This creates a CS5535/CS5536 GPIO driver which uses a gpio_chip backend
(allowing GPIO users to use the generic GPIO API if desired) while also
allowing architecture-specific users directly (via the cs5535_gpio_*
functions).
Tested on an OLPC machine. Some Leemotes also use CS5536 (with a mips
cpu), which is why this is in drivers/gpio rather than arch/x86.
Currently, it conflicts with older geode GPIO support; once MFGPT support
is reworked to also be more generic, the older geode code will be removed.
Signed-off-by: Andres Salomon <dilinger@collabora.co.uk>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: David Brownell <david-b@pacbell.net>
Reviewed-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/gpio/Kconfig | 10 | ||||
-rw-r--r-- | drivers/gpio/Makefile | 1 | ||||
-rw-r--r-- | drivers/gpio/cs5535-gpio.c | 282 |
3 files changed, 293 insertions, 0 deletions
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 2ad0128c63c..df4b82d1348 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -174,6 +174,16 @@ config GPIO_ADP5520 comment "PCI GPIO expanders:" +config GPIO_CS5535 + tristate "AMD CS5535/CS5536 GPIO support" + depends on PCI && !CS5535_GPIO && !MGEODE_LX + help + The AMD CS5535 and CS5536 southbridges support 28 GPIO pins that + can be used for quite a number of things. The CS5535/6 is found on + AMD Geode and Lemote Yeeloong devices. + + If unsure, say N. + config GPIO_BT8XX tristate "BT8XX GPIO abuser" depends on PCI && VIDEO_BT848=n diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 00a532c9a1e..270b6d7839f 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_GPIO_PL061) += pl061.o obj-$(CONFIG_GPIO_TWL4030) += twl4030-gpio.o obj-$(CONFIG_GPIO_UCB1400) += ucb1400_gpio.o obj-$(CONFIG_GPIO_XILINX) += xilinx_gpio.o +obj-$(CONFIG_GPIO_CS5535) += cs5535-gpio.o obj-$(CONFIG_GPIO_BT8XX) += bt8xxgpio.o obj-$(CONFIG_GPIO_VR41XX) += vr41xx_giu.o obj-$(CONFIG_GPIO_WM831X) += wm831x-gpio.o diff --git a/drivers/gpio/cs5535-gpio.c b/drivers/gpio/cs5535-gpio.c new file mode 100644 index 00000000000..56138893819 --- /dev/null +++ b/drivers/gpio/cs5535-gpio.c @@ -0,0 +1,282 @@ +/* + * AMD CS5535/CS5536 GPIO driver + * Copyright (C) 2006 Advanced Micro Devices, Inc. + * Copyright (C) 2007-2009 Andres Salomon <dilinger@collabora.co.uk> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public License + * as published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/spinlock.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/gpio.h> +#include <linux/io.h> +#include <linux/cs5535.h> + +#define DRV_NAME "cs5535-gpio" +#define GPIO_BAR 1 + +static struct cs5535_gpio_chip { + struct gpio_chip chip; + resource_size_t base; + + struct pci_dev *pdev; + spinlock_t lock; +} cs5535_gpio_chip; + +/* + * The CS5535/CS5536 GPIOs support a number of extra features not defined + * by the gpio_chip API, so these are exported. For a full list of the + * registers, see include/linux/cs5535.h. + */ + +static void __cs5535_gpio_set(struct cs5535_gpio_chip *chip, unsigned offset, + unsigned int reg) +{ + if (offset < 16) + /* low bank register */ + outl(1 << offset, chip->base + reg); + else + /* high bank register */ + outl(1 << (offset - 16), chip->base + 0x80 + reg); +} + +void cs5535_gpio_set(unsigned offset, unsigned int reg) +{ + struct cs5535_gpio_chip *chip = &cs5535_gpio_chip; + unsigned long flags; + + spin_lock_irqsave(&chip->lock, flags); + __cs5535_gpio_set(chip, offset, reg); + spin_unlock_irqrestore(&chip->lock, flags); +} +EXPORT_SYMBOL_GPL(cs5535_gpio_set); + +static void __cs5535_gpio_clear(struct cs5535_gpio_chip *chip, unsigned offset, + unsigned int reg) +{ + if (offset < 16) + /* low bank register */ + outl(1 << (offset + 16), chip->base + reg); + else + /* high bank register */ + outl(1 << offset, chip->base + 0x80 + reg); +} + +void cs5535_gpio_clear(unsigned offset, unsigned int reg) +{ + struct cs5535_gpio_chip *chip = &cs5535_gpio_chip; + unsigned long flags; + + spin_lock_irqsave(&chip->lock, flags); + __cs5535_gpio_clear(chip, offset, reg); + spin_unlock_irqrestore(&chip->lock, flags); +} +EXPORT_SYMBOL_GPL(cs5535_gpio_clear); + +int cs5535_gpio_isset(unsigned offset, unsigned int reg) +{ + struct cs5535_gpio_chip *chip = &cs5535_gpio_chip; + unsigned long flags; + long val; + + spin_lock_irqsave(&chip->lock, flags); + if (offset < 16) + /* low bank register */ + val = inl(chip->base + reg); + else { + /* high bank register */ + val = inl(chip->base + 0x80 + reg); + offset -= 16; + } + spin_unlock_irqrestore(&chip->lock, flags); + + return (val & (1 << offset)) ? 1 : 0; +} +EXPORT_SYMBOL_GPL(cs5535_gpio_isset); + +/* + * Generic gpio_chip API support. + */ + +static int chip_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + return cs5535_gpio_isset(offset, GPIO_OUTPUT_VAL); +} + +static void chip_gpio_set(struct gpio_chip *chip, unsigned offset, int val) +{ + if (val) + cs5535_gpio_set(offset, GPIO_OUTPUT_VAL); + else + cs5535_gpio_clear(offset, GPIO_OUTPUT_VAL); +} + +static int chip_direction_input(struct gpio_chip *c, unsigned offset) +{ + struct cs5535_gpio_chip *chip = (struct cs5535_gpio_chip *) c; + unsigned long flags; + + spin_lock_irqsave(&chip->lock, flags); + __cs5535_gpio_set(chip, offset, GPIO_INPUT_ENABLE); + spin_unlock_irqrestore(&chip->lock, flags); + + return 0; +} + +static int chip_direction_output(struct gpio_chip *c, unsigned offset, int val) +{ + struct cs5535_gpio_chip *chip = (struct cs5535_gpio_chip *) c; + unsigned long flags; + + spin_lock_irqsave(&chip->lock, flags); + + __cs5535_gpio_set(chip, offset, GPIO_OUTPUT_ENABLE); + if (val) + __cs5535_gpio_set(chip, offset, GPIO_OUTPUT_VAL); + else + __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_VAL); + + spin_unlock_irqrestore(&chip->lock, flags); + + return 0; +} + +static struct cs5535_gpio_chip cs5535_gpio_chip = { + .chip = { + .owner = THIS_MODULE, + .label = DRV_NAME, + + .base = 0, + .ngpio = 28, + + .get = chip_gpio_get, + .set = chip_gpio_set, + + .direction_input = chip_direction_input, + .direction_output = chip_direction_output, + }, +}; + +static int __init cs5535_gpio_probe(struct pci_dev *pdev, + const struct pci_device_id *pci_id) +{ + int err; + + /* There are two ways to get the GPIO base address; one is by + * fetching it from MSR_LBAR_GPIO, the other is by reading the + * PCI BAR info. The latter method is easier (especially across + * different architectures), so we'll stick with that for now. If + * it turns out to be unreliable in the face of crappy BIOSes, we + * can always go back to using MSRs.. */ + + err = pci_enable_device_io(pdev); + if (err) { + dev_err(&pdev->dev, "can't enable device IO\n"); + goto done; + } + + err = pci_request_region(pdev, GPIO_BAR, DRV_NAME); + if (err) { + dev_err(&pdev->dev, "can't alloc PCI BAR #%d\n", GPIO_BAR); + goto done; + } + + /* set up the driver-specific struct */ + cs5535_gpio_chip.base = pci_resource_start(pdev, GPIO_BAR); + cs5535_gpio_chip.pdev = pdev; + spin_lock_init(&cs5535_gpio_chip.lock); + + dev_info(&pdev->dev, "allocated PCI BAR #%d: base 0x%llx\n", GPIO_BAR, + (unsigned long long) cs5535_gpio_chip.base); + + /* finally, register with the generic GPIO API */ + err = gpiochip_add(&cs5535_gpio_chip.chip); + if (err) { + dev_err(&pdev->dev, "failed to register gpio chip\n"); + goto release_region; + } + + printk(KERN_INFO DRV_NAME ": GPIO support successfully loaded.\n"); + return 0; + +release_region: + pci_release_region(pdev, GPIO_BAR); +done: + return err; +} + +static void __exit cs5535_gpio_remove(struct pci_dev *pdev) +{ + int err; + + err = gpiochip_remove(&cs5535_gpio_chip.chip); + if (err) { + /* uhh? */ + dev_err(&pdev->dev, "unable to remove gpio_chip?\n"); + } + pci_release_region(pdev, GPIO_BAR); +} + +static struct pci_device_id cs5535_gpio_pci_tbl[] = { + { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_CS5535_ISA) }, + { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA) }, + { 0, }, +}; +MODULE_DEVICE_TABLE(pci, cs5535_gpio_pci_tbl); + +/* + * We can't use the standard PCI driver registration stuff here, since + * that allows only one driver to bind to each PCI device (and we want + * multiple drivers to be able to bind to the device). Instead, manually + * scan for the PCI device, request a single region, and keep track of the + * devices that we're using. + */ + +static int __init cs5535_gpio_scan_pci(void) +{ + struct pci_dev *pdev; + int err = -ENODEV; + int i; + + for (i = 0; i < ARRAY_SIZE(cs5535_gpio_pci_tbl); i++) { + pdev = pci_get_device(cs5535_gpio_pci_tbl[i].vendor, + cs5535_gpio_pci_tbl[i].device, NULL); + if (pdev) { + err = cs5535_gpio_probe(pdev, &cs5535_gpio_pci_tbl[i]); + if (err) + pci_dev_put(pdev); + + /* we only support a single CS5535/6 southbridge */ + break; + } + } + + return err; +} + +static void __exit cs5535_gpio_free_pci(void) +{ + cs5535_gpio_remove(cs5535_gpio_chip.pdev); + pci_dev_put(cs5535_gpio_chip.pdev); +} + +static int __init cs5535_gpio_init(void) +{ + return cs5535_gpio_scan_pci(); +} + +static void __exit cs5535_gpio_exit(void) +{ + cs5535_gpio_free_pci(); +} + +module_init(cs5535_gpio_init); +module_exit(cs5535_gpio_exit); + +MODULE_AUTHOR("Andres Salomon <dilinger@collabora.co.uk>"); +MODULE_DESCRIPTION("AMD CS5535/CS5536 GPIO driver"); +MODULE_LICENSE("GPL"); |