/* * GPIO driver for AMD 8111 south bridges * * Copyright (c) 2012 Dmitry Eremin-Solenikov * * Based on the AMD RNG driver: * Copyright 2005 (c) MontaVista Software, Inc. * with the majority of the code coming from: * * Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG) * (c) Copyright 2003 Red Hat Inc * * derived from * * Hardware driver for the AMD 768 Random Number Generator (RNG) * (c) Copyright 2001 Red Hat Inc * * derived from * * Hardware driver for Intel i810 Random Number Generator (RNG) * Copyright 2000,2001 Jeff Garzik * Copyright 2000,2001 Philipp Rumpf * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include #include #include #include #include #define PMBASE_OFFSET 0xb0 #define PMBASE_SIZE 0x30 #define AMD_REG_GPIO(i) (0x10 + (i)) #define AMD_GPIO_LTCH_STS 0x40 /* Latch status, w1 */ #define AMD_GPIO_RTIN 0x20 /* Real Time in, ro */ #define AMD_GPIO_DEBOUNCE 0x10 /* Debounce, rw */ #define AMD_GPIO_MODE_MASK 0x0c /* Pin Mode Select, rw */ #define AMD_GPIO_MODE_IN 0x00 #define AMD_GPIO_MODE_OUT 0x04 /* Enable alternative (e.g. clkout, IRQ, etc) function of the pin */ #define AMD_GPIO_MODE_ALTFN 0x08 /* Or 0x09 */ #define AMD_GPIO_X_MASK 0x03 /* In/Out specific, rw */ #define AMD_GPIO_X_IN_ACTIVEHI 0x01 /* Active High */ #define AMD_GPIO_X_IN_LATCH 0x02 /* Latched version is selected */ #define AMD_GPIO_X_OUT_LOW 0x00 #define AMD_GPIO_X_OUT_HI 0x01 #define AMD_GPIO_X_OUT_CLK0 0x02 #define AMD_GPIO_X_OUT_CLK1 0x03 /* * Data for PCI driver interface * * This data only exists for exporting the supported * PCI ids via MODULE_DEVICE_TABLE. We do not actually * register a pci_driver, because someone else might one day * want to register another driver on the same PCI id. */ static const struct pci_device_id pci_tbl[] = { { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8111_SMBUS), 0 }, { 0, }, /* terminate list */ }; MODULE_DEVICE_TABLE(pci, pci_tbl); struct amd_gpio { struct gpio_chip chip; u32 pmbase; void __iomem *pm; struct pci_dev *pdev; spinlock_t lock; /* guards hw registers and orig table */ u8 orig[32]; }; #define to_agp(chip) container_of(chip, struct amd_gpio, chip) static int amd_gpio_request(struct gpio_chip *chip, unsigned offset) { struct amd_gpio *agp = to_agp(chip); agp->orig[offset] = ioread8(agp->pm + AMD_REG_GPIO(offset)) & (AMD_GPIO_DEBOUNCE | AMD_GPIO_MODE_MASK | AMD_GPIO_X_MASK); dev_dbg(&agp->pdev->dev, "Requested gpio %d, data %x\n", offset, agp->orig[offset]); return 0; } static void amd_gpio_free(struct gpio_chip *chip, unsigned offset) { struct amd_gpio *agp = to_agp(chip); dev_dbg(&agp->pdev->dev, "Freed gpio %d, data %x\n", offset, agp->orig[offset]); iowrite8(agp->orig[offset], agp->pm + AMD_REG_GPIO(offset)); } static void amd_gpio_set(struct gpio_chip *chip, unsigned offset, int value) { struct amd_gpio *agp = to_agp(chip); u8 temp; unsigned long flags; spin_lock_irqsave(&agp->lock, flags); temp = ioread8(agp->pm + AMD_REG_GPIO(offset)); temp = (temp & AMD_GPIO_DEBOUNCE) | AMD_GPIO_MODE_OUT | (value ? AMD_GPIO_X_OUT_HI : AMD_GPIO_X_OUT_LOW); iowrite8(temp, agp->pm + AMD_REG_GPIO(offset)); spin_unlock_irqrestore(&agp->lock, flags); dev_dbg(&agp->pdev->dev, "Setting gpio %d, value %d, reg=%02x\n", offset, !!value, temp); } static int amd_gpio_get(struct gpio_chip *chip, unsigned offset) { struct amd_gpio *agp = to_agp(chip); u8 temp; temp = ioread8(agp->pm + AMD_REG_GPIO(offset)); dev_dbg(&agp->pdev->dev, "Getting gpio %d, reg=%02x\n", offset, temp); return (temp & AMD_GPIO_RTIN) ? 1 : 0; } static int amd_gpio_dirout(struct gpio_chip *chip, unsigned offset, int value) { struct amd_gpio *agp = to_agp(chip); u8 temp; unsigned long flags; spin_lock_irqsave(&agp->lock, flags); temp = ioread8(agp->pm + AMD_REG_GPIO(offset)); temp = (temp & AMD_GPIO_DEBOUNCE) | AMD_GPIO_MODE_OUT | (value ? AMD_GPIO_X_OUT_HI : AMD_GPIO_X_OUT_LOW); iowrite8(temp, agp->pm + AMD_REG_GPIO(offset)); spin_unlock_irqrestore(&agp->lock, flags); dev_dbg(&agp->pdev->dev, "Dirout gpio %d, value %d, reg=%02x\n", offset, !!value, temp); return 0; } static int amd_gpio_dirin(struct gpio_chip *chip, unsigned offset) { struct amd_gpio *agp = to_agp(chip); u8 temp; unsigned long flags; spin_lock_irqsave(&agp->lock, flags); temp = ioread8(agp->pm + AMD_REG_GPIO(offset)); temp = (temp & AMD_GPIO_DEBOUNCE) | AMD_GPIO_MODE_IN; iowrite8(temp, agp->pm + AMD_REG_GPIO(offset)); spin_unlock_irqrestore(&agp->lock, flags); dev_dbg(&agp->pdev->dev, "Dirin gpio %d, reg=%02x\n", offset, temp); return 0; } static struct amd_gpio gp = { .chip = { .label = "AMD GPIO", .owner = THIS_MODULE, .base = -1, .ngpio = 32, .request = amd_gpio_request, .free = amd_gpio_free, .set = amd_gpio_set, .get = amd_gpio_get, .direction_output = amd_gpio_dirout, .direction_input = amd_gpio_dirin, }, }; static int __init amd_gpio_init(void) { int err = -ENODEV; struct pci_dev *pdev = NULL; const struct pci_device_id *ent; /* We look for our device - AMD South Bridge * I don't know about a system with two such bridges, * so we can assume that there is max. one device. * * We can't use plain pci_driver mechanism, * as the device is really a multiple function device, * main driver that binds to the pci_device is an smbus * driver and have to find & bind to the device this way. */ for_each_pci_dev(pdev) { ent = pci_match_id(pci_tbl, pdev); if (ent) goto found; } /* Device not found. */ goto out; found: err = pci_read_config_dword(pdev, 0x58, &gp.pmbase); if (err) goto out; err = -EIO; gp.pmbase &= 0x0000FF00; if (gp.pmbase == 0) goto out; if (!request_region(gp.pmbase + PMBASE_OFFSET, PMBASE_SIZE, "AMD GPIO")) { dev_err(&pdev->dev, "AMD GPIO region 0x%x already in use!\n", gp.pmbase + PMBASE_OFFSET); err = -EBUSY; goto out; } gp.pm = ioport_map(gp.pmbase + PMBASE_OFFSET, PMBASE_SIZE); if (!gp.pm) { dev_err(&pdev->dev, "Couldn't map io port into io memory\n"); release_region(gp.pmbase + PMBASE_OFFSET, PMBASE_SIZE); err = -ENOMEM; goto out; } gp.pdev = pdev; gp.chip.dev = &pdev->dev; spin_lock_init(&gp.lock); printk(KERN_INFO "AMD-8111 GPIO detected\n"); err = gpiochip_add(&gp.chip); if (err) { printk(KERN_ERR "GPIO registering failed (%d)\n", err); ioport_unmap(gp.pm); release_region(gp.pmbase + PMBASE_OFFSET, PMBASE_SIZE); goto out; } out: return err; } static void __exit amd_gpio_exit(void) { gpiochip_remove(&gp.chip); ioport_unmap(gp.pm); release_region(gp.pmbase + PMBASE_OFFSET, PMBASE_SIZE); } module_init(amd_gpio_init); module_exit(amd_gpio_exit); MODULE_AUTHOR("The Linux Kernel team"); MODULE_DESCRIPTION("GPIO driver for AMD chipsets"); MODULE_LICENSE("GPL");