| /* |
| * RDC321x GPIO driver |
| * |
| * Copyright (C) 2008, Volker Weiss <dev@tintuc.de> |
| * Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * 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; if not, write to the Free Software |
| * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| * |
| */ |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/spinlock.h> |
| #include <linux/platform_device.h> |
| #include <linux/pci.h> |
| #include <linux/gpio.h> |
| #include <linux/mfd/rdc321x.h> |
| #include <linux/slab.h> |
| |
| struct rdc321x_gpio { |
| spinlock_t lock; |
| struct pci_dev *sb_pdev; |
| u32 data_reg[2]; |
| int reg1_ctrl_base; |
| int reg1_data_base; |
| int reg2_ctrl_base; |
| int reg2_data_base; |
| struct gpio_chip chip; |
| }; |
| |
| /* read GPIO pin */ |
| static int rdc_gpio_get_value(struct gpio_chip *chip, unsigned gpio) |
| { |
| struct rdc321x_gpio *gpch; |
| u32 value = 0; |
| int reg; |
| |
| gpch = container_of(chip, struct rdc321x_gpio, chip); |
| reg = gpio < 32 ? gpch->reg1_data_base : gpch->reg2_data_base; |
| |
| spin_lock(&gpch->lock); |
| pci_write_config_dword(gpch->sb_pdev, reg, |
| gpch->data_reg[gpio < 32 ? 0 : 1]); |
| pci_read_config_dword(gpch->sb_pdev, reg, &value); |
| spin_unlock(&gpch->lock); |
| |
| return (1 << (gpio & 0x1f)) & value ? 1 : 0; |
| } |
| |
| static void rdc_gpio_set_value_impl(struct gpio_chip *chip, |
| unsigned gpio, int value) |
| { |
| struct rdc321x_gpio *gpch; |
| int reg = (gpio < 32) ? 0 : 1; |
| |
| gpch = container_of(chip, struct rdc321x_gpio, chip); |
| |
| if (value) |
| gpch->data_reg[reg] |= 1 << (gpio & 0x1f); |
| else |
| gpch->data_reg[reg] &= ~(1 << (gpio & 0x1f)); |
| |
| pci_write_config_dword(gpch->sb_pdev, |
| reg ? gpch->reg2_data_base : gpch->reg1_data_base, |
| gpch->data_reg[reg]); |
| } |
| |
| /* set GPIO pin to value */ |
| static void rdc_gpio_set_value(struct gpio_chip *chip, |
| unsigned gpio, int value) |
| { |
| struct rdc321x_gpio *gpch; |
| |
| gpch = container_of(chip, struct rdc321x_gpio, chip); |
| spin_lock(&gpch->lock); |
| rdc_gpio_set_value_impl(chip, gpio, value); |
| spin_unlock(&gpch->lock); |
| } |
| |
| static int rdc_gpio_config(struct gpio_chip *chip, |
| unsigned gpio, int value) |
| { |
| struct rdc321x_gpio *gpch; |
| int err; |
| u32 reg; |
| |
| gpch = container_of(chip, struct rdc321x_gpio, chip); |
| |
| spin_lock(&gpch->lock); |
| err = pci_read_config_dword(gpch->sb_pdev, gpio < 32 ? |
| gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, ®); |
| if (err) |
| goto unlock; |
| |
| reg |= 1 << (gpio & 0x1f); |
| |
| err = pci_write_config_dword(gpch->sb_pdev, gpio < 32 ? |
| gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, reg); |
| if (err) |
| goto unlock; |
| |
| rdc_gpio_set_value_impl(chip, gpio, value); |
| |
| unlock: |
| spin_unlock(&gpch->lock); |
| |
| return err; |
| } |
| |
| /* configure GPIO pin as input */ |
| static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) |
| { |
| return rdc_gpio_config(chip, gpio, 1); |
| } |
| |
| /* |
| * Cache the initial value of both GPIO data registers |
| */ |
| static int rdc321x_gpio_probe(struct platform_device *pdev) |
| { |
| int err; |
| struct resource *r; |
| struct rdc321x_gpio *rdc321x_gpio_dev; |
| struct rdc321x_gpio_pdata *pdata; |
| |
| pdata = pdev->dev.platform_data; |
| if (!pdata) { |
| dev_err(&pdev->dev, "no platform data supplied\n"); |
| return -ENODEV; |
| } |
| |
| rdc321x_gpio_dev = kzalloc(sizeof(struct rdc321x_gpio), GFP_KERNEL); |
| if (!rdc321x_gpio_dev) { |
| dev_err(&pdev->dev, "failed to allocate private data\n"); |
| return -ENOMEM; |
| } |
| |
| r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg1"); |
| if (!r) { |
| dev_err(&pdev->dev, "failed to get gpio-reg1 resource\n"); |
| err = -ENODEV; |
| goto out_free; |
| } |
| |
| spin_lock_init(&rdc321x_gpio_dev->lock); |
| rdc321x_gpio_dev->sb_pdev = pdata->sb_pdev; |
| rdc321x_gpio_dev->reg1_ctrl_base = r->start; |
| rdc321x_gpio_dev->reg1_data_base = r->start + 0x4; |
| |
| r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg2"); |
| if (!r) { |
| dev_err(&pdev->dev, "failed to get gpio-reg2 resource\n"); |
| err = -ENODEV; |
| goto out_free; |
| } |
| |
| rdc321x_gpio_dev->reg2_ctrl_base = r->start; |
| rdc321x_gpio_dev->reg2_data_base = r->start + 0x4; |
| |
| rdc321x_gpio_dev->chip.label = "rdc321x-gpio"; |
| rdc321x_gpio_dev->chip.owner = THIS_MODULE; |
| rdc321x_gpio_dev->chip.direction_input = rdc_gpio_direction_input; |
| rdc321x_gpio_dev->chip.direction_output = rdc_gpio_config; |
| rdc321x_gpio_dev->chip.get = rdc_gpio_get_value; |
| rdc321x_gpio_dev->chip.set = rdc_gpio_set_value; |
| rdc321x_gpio_dev->chip.base = 0; |
| rdc321x_gpio_dev->chip.ngpio = pdata->max_gpios; |
| |
| platform_set_drvdata(pdev, rdc321x_gpio_dev); |
| |
| /* This might not be, what others (BIOS, bootloader, etc.) |
| wrote to these registers before, but it's a good guess. Still |
| better than just using 0xffffffff. */ |
| err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev, |
| rdc321x_gpio_dev->reg1_data_base, |
| &rdc321x_gpio_dev->data_reg[0]); |
| if (err) |
| goto out_drvdata; |
| |
| err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev, |
| rdc321x_gpio_dev->reg2_data_base, |
| &rdc321x_gpio_dev->data_reg[1]); |
| if (err) |
| goto out_drvdata; |
| |
| dev_info(&pdev->dev, "registering %d GPIOs\n", |
| rdc321x_gpio_dev->chip.ngpio); |
| return gpiochip_add(&rdc321x_gpio_dev->chip); |
| |
| out_drvdata: |
| platform_set_drvdata(pdev, NULL); |
| out_free: |
| kfree(rdc321x_gpio_dev); |
| return err; |
| } |
| |
| static int rdc321x_gpio_remove(struct platform_device *pdev) |
| { |
| int ret; |
| struct rdc321x_gpio *rdc321x_gpio_dev = platform_get_drvdata(pdev); |
| |
| ret = gpiochip_remove(&rdc321x_gpio_dev->chip); |
| if (ret) |
| dev_err(&pdev->dev, "failed to unregister chip\n"); |
| |
| kfree(rdc321x_gpio_dev); |
| platform_set_drvdata(pdev, NULL); |
| |
| return ret; |
| } |
| |
| static struct platform_driver rdc321x_gpio_driver = { |
| .driver.name = "rdc321x-gpio", |
| .driver.owner = THIS_MODULE, |
| .probe = rdc321x_gpio_probe, |
| .remove = rdc321x_gpio_remove, |
| }; |
| |
| module_platform_driver(rdc321x_gpio_driver); |
| |
| MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>"); |
| MODULE_DESCRIPTION("RDC321x GPIO driver"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:rdc321x-gpio"); |