diff options
Diffstat (limited to 'drivers/gpio/cs5535-gpio.c')
| -rw-r--r-- | drivers/gpio/cs5535-gpio.c | 355 |
1 files changed, 355 insertions, 0 deletions
diff --git a/drivers/gpio/cs5535-gpio.c b/drivers/gpio/cs5535-gpio.c new file mode 100644 index 00000000000..0fdbe94f24a --- /dev/null +++ b/drivers/gpio/cs5535-gpio.c @@ -0,0 +1,355 @@ +/* + * 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 + +/* + * Some GPIO pins + * 31-29,23 : reserved (always mask out) + * 28 : Power Button + * 26 : PME# + * 22-16 : LPC + * 14,15 : SMBus + * 9,8 : UART1 + * 7 : PCI INTB + * 3,4 : UART2/DDC + * 2 : IDE_IRQ0 + * 1 : AC_BEEP + * 0 : PCI INTA + * + * If a mask was not specified, allow all except + * reserved and Power Button + */ +#define GPIO_DEFAULT_MASK 0x0F7FFFFF + +static ulong mask = GPIO_DEFAULT_MASK; +module_param_named(mask, mask, ulong, 0444); +MODULE_PARM_DESC(mask, "GPIO channel mask."); + +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_request(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); + + /* check if this pin is available */ + if ((mask & (1 << offset)) == 0) { + dev_info(&chip->pdev->dev, + "pin %u is not available (check mask)\n", offset); + spin_unlock_irqrestore(&chip->lock, flags); + return -EINVAL; + } + + /* disable output aux 1 & 2 on this pin */ + __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_AUX1); + __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_AUX2); + + /* disable input aux 1 on this pin */ + __cs5535_gpio_clear(chip, offset, GPIO_INPUT_AUX1); + + spin_unlock_irqrestore(&chip->lock, flags); + + return 0; +} + +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 char *cs5535_gpio_names[] = { + "GPIO0", "GPIO1", "GPIO2", "GPIO3", + "GPIO4", "GPIO5", "GPIO6", "GPIO7", + "GPIO8", "GPIO9", "GPIO10", "GPIO11", + "GPIO12", "GPIO13", "GPIO14", "GPIO15", + "GPIO16", "GPIO17", "GPIO18", "GPIO19", + "GPIO20", "GPIO21", "GPIO22", NULL, + "GPIO24", "GPIO25", "GPIO26", "GPIO27", + "GPIO28", NULL, NULL, NULL, +}; + +static struct cs5535_gpio_chip cs5535_gpio_chip = { + .chip = { + .owner = THIS_MODULE, + .label = DRV_NAME, + + .base = 0, + .ngpio = 32, + .names = cs5535_gpio_names, + .request = chip_gpio_request, + + .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; + ulong mask_orig = mask; + + /* 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); + + /* mask out reserved pins */ + mask &= 0x1F7FFFFF; + + /* do not allow pin 28, Power Button, as there's special handling + * in the PMC needed. (note 12, p. 48) */ + mask &= ~(1 << 28); + + if (mask_orig != mask) + dev_info(&pdev->dev, "mask changed from 0x%08lX to 0x%08lX\n", + mask_orig, mask); + + /* finally, register with the generic GPIO API */ + err = gpiochip_add(&cs5535_gpio_chip.chip); + if (err) + goto release_region; + + dev_info(&pdev->dev, 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"); |