arm: vt8500: gpio: Devicetree support for arch-vt8500
authorTony Prisk <linux@prisktech.co.nz>
Wed, 8 Aug 2012 01:05:55 +0000 (13:05 +1200)
committerTony Prisk <linux@prisktech.co.nz>
Fri, 21 Sep 2012 07:23:59 +0000 (19:23 +1200)
Converted the existing arch-vt8500 gpio to a platform_device.
Added support for WM8505 and WM8650 GPIO controllers.
Replaced existing readl/writel calls with _relaxed variants.
Replaced existing unsigned variables with u32 to match register size.

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
drivers/gpio/Kconfig
drivers/gpio/Makefile
drivers/gpio/gpio-vt8500.c [new file with mode: 0644]

index ba7926f5c0996ea78f571ab5e87de2a3aa2c490e..a00b828b1643ddfbcd90f219525a93fe15efc5af 100644 (file)
@@ -183,6 +183,12 @@ config GPIO_STA2X11
          Say yes here to support the STA2x11/ConneXt GPIO device.
          The GPIO module has 128 GPIO pins with alternate functions.
 
+config GPIO_VT8500
+       bool "VIA/Wondermedia SoC GPIO Support"
+       depends on ARCH_VT8500
+       help
+         Say yes here to support the VT8500/WM8505/WM8650 GPIO controller.
+
 config GPIO_XILINX
        bool "Xilinx GPIO support"
        depends on PPC_OF || MICROBLAZE
index 153caceeb0530df7a7e5932421b7f2d48fee3780..a288142ad99879fd1da7484bcca4f4fd5586e567 100644 (file)
@@ -69,6 +69,7 @@ obj-$(CONFIG_GPIO_TPS65912)   += gpio-tps65912.o
 obj-$(CONFIG_GPIO_TWL4030)     += gpio-twl4030.o
 obj-$(CONFIG_GPIO_UCB1400)     += gpio-ucb1400.o
 obj-$(CONFIG_GPIO_VR41XX)      += gpio-vr41xx.o
+obj-$(CONFIG_GPIO_VT8500)      += gpio-vt8500.o
 obj-$(CONFIG_GPIO_VX855)       += gpio-vx855.o
 obj-$(CONFIG_GPIO_WM831X)      += gpio-wm831x.o
 obj-$(CONFIG_GPIO_WM8350)      += gpio-wm8350.o
diff --git a/drivers/gpio/gpio-vt8500.c b/drivers/gpio/gpio-vt8500.c
new file mode 100644 (file)
index 0000000..bcd8e4a
--- /dev/null
@@ -0,0 +1,316 @@
+/* drivers/gpio/gpio-vt8500.c
+ *
+ * Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz>
+ * Based on arch/arm/mach-vt8500/gpio.c:
+ * - Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/bitops.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_device.h>
+
+/*
+       We handle GPIOs by bank, each bank containing up to 32 GPIOs covered
+       by one set of registers (although not all may be valid).
+
+       Because different SoC's have different register offsets, we pass the
+       register offsets as data in vt8500_gpio_dt_ids[].
+
+       A value of NO_REG is used to indicate that this register is not
+       supported. Only used for ->en at the moment.
+*/
+
+#define NO_REG 0xFFFF
+
+/*
+ * struct vt8500_gpio_bank_regoffsets
+ * @en: offset to enable register of the bank
+ * @dir: offset to direction register of the bank
+ * @data_out: offset to the data out register of the bank
+ * @data_in: offset to the data in register of the bank
+ * @ngpio: highest valid pin in this bank
+ */
+
+struct vt8500_gpio_bank_regoffsets {
+       unsigned int    en;
+       unsigned int    dir;
+       unsigned int    data_out;
+       unsigned int    data_in;
+       unsigned char   ngpio;
+};
+
+struct vt8500_gpio_data {
+       unsigned int                            num_banks;
+       struct vt8500_gpio_bank_regoffsets      banks[];
+};
+
+#define VT8500_BANK(__en, __dir, __out, __in, __ngpio)         \
+{                                                              \
+       .en = __en,                                             \
+       .dir = __dir,                                           \
+       .data_out = __out,                                      \
+       .data_in = __in,                                        \
+       .ngpio = __ngpio,                                       \
+}
+
+static struct vt8500_gpio_data vt8500_data = {
+       .num_banks      = 7,
+       .banks  = {
+               VT8500_BANK(0x00, 0x20, 0x40, 0x60, 26),
+               VT8500_BANK(0x04, 0x24, 0x44, 0x64, 28),
+               VT8500_BANK(0x08, 0x28, 0x48, 0x68, 31),
+               VT8500_BANK(0x0C, 0x2C, 0x4C, 0x6C, 19),
+               VT8500_BANK(0x10, 0x30, 0x50, 0x70, 19),
+               VT8500_BANK(0x14, 0x34, 0x54, 0x74, 23),
+               VT8500_BANK(NO_REG, 0x3C, 0x5C, 0x7C, 9),
+       },
+};
+
+static struct vt8500_gpio_data wm8505_data = {
+       .num_banks      = 10,
+       .banks  = {
+               VT8500_BANK(0x40, 0x68, 0x90, 0xB8, 8),
+               VT8500_BANK(0x44, 0x6C, 0x94, 0xBC, 32),
+               VT8500_BANK(0x48, 0x70, 0x98, 0xC0, 6),
+               VT8500_BANK(0x4C, 0x74, 0x9C, 0xC4, 16),
+               VT8500_BANK(0x50, 0x78, 0xA0, 0xC8, 25),
+               VT8500_BANK(0x54, 0x7C, 0xA4, 0xCC, 5),
+               VT8500_BANK(0x58, 0x80, 0xA8, 0xD0, 5),
+               VT8500_BANK(0x5C, 0x84, 0xAC, 0xD4, 12),
+               VT8500_BANK(0x60, 0x88, 0xB0, 0xD8, 16),
+               VT8500_BANK(0x64, 0x8C, 0xB4, 0xDC, 22),
+       },
+};
+
+/*
+ * No information about which bits are valid so we just make
+ * them all available until its figured out.
+ */
+static struct vt8500_gpio_data wm8650_data = {
+       .num_banks      = 9,
+       .banks  = {
+               VT8500_BANK(0x40, 0x80, 0xC0, 0x00, 32),
+               VT8500_BANK(0x44, 0x84, 0xC4, 0x04, 32),
+               VT8500_BANK(0x48, 0x88, 0xC8, 0x08, 32),
+               VT8500_BANK(0x4C, 0x8C, 0xCC, 0x0C, 32),
+               VT8500_BANK(0x50, 0x90, 0xD0, 0x10, 32),
+               VT8500_BANK(0x54, 0x94, 0xD4, 0x14, 32),
+               VT8500_BANK(0x58, 0x98, 0xD8, 0x18, 32),
+               VT8500_BANK(0x5C, 0x9C, 0xDC, 0x1C, 32),
+               VT8500_BANK(0x7C, 0xBC, 0xFC, 0x3C, 32),
+       },
+};
+
+struct vt8500_gpio_chip {
+       struct gpio_chip                chip;
+
+       const struct vt8500_gpio_bank_regoffsets *regs;
+       void __iomem    *base;
+};
+
+
+#define to_vt8500(__chip) container_of(__chip, struct vt8500_gpio_chip, chip)
+
+static int vt8500_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+       u32 val;
+       struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+
+       if (vt8500_chip->regs->en == NO_REG)
+               return 0;
+
+       val = readl_relaxed(vt8500_chip->base + vt8500_chip->regs->en);
+       val |= BIT(offset);
+       writel_relaxed(val, vt8500_chip->base + vt8500_chip->regs->en);
+
+       return 0;
+}
+
+static void vt8500_gpio_free(struct gpio_chip *chip, unsigned offset)
+{
+       struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+       u32 val;
+
+       if (vt8500_chip->regs->en == NO_REG)
+               return;
+
+       val = readl_relaxed(vt8500_chip->base + vt8500_chip->regs->en);
+       val &= ~BIT(offset);
+       writel_relaxed(val, vt8500_chip->base + vt8500_chip->regs->en);
+}
+
+static int vt8500_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+       struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+
+       u32 val = readl_relaxed(vt8500_chip->base + vt8500_chip->regs->dir);
+       val &= ~BIT(offset);
+       writel_relaxed(val, vt8500_chip->base + vt8500_chip->regs->dir);
+
+       return 0;
+}
+
+static int vt8500_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
+                                                               int value)
+{
+       struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+
+       u32 val = readl_relaxed(vt8500_chip->base + vt8500_chip->regs->dir);
+       val |= BIT(offset);
+       writel_relaxed(val, vt8500_chip->base + vt8500_chip->regs->dir);
+
+       if (value) {
+               val = readl_relaxed(vt8500_chip->base +
+                                               vt8500_chip->regs->data_out);
+               val |= BIT(offset);
+               writel_relaxed(val, vt8500_chip->base +
+                                               vt8500_chip->regs->data_out);
+       }
+       return 0;
+}
+
+static int vt8500_gpio_get_value(struct gpio_chip *chip, unsigned offset)
+{
+       struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+
+       return (readl_relaxed(vt8500_chip->base + vt8500_chip->regs->data_in) >>
+                                                               offset) & 1;
+}
+
+static void vt8500_gpio_set_value(struct gpio_chip *chip, unsigned offset,
+                                                               int value)
+{
+       struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+
+       u32 val = readl_relaxed(vt8500_chip->base +
+                                               vt8500_chip->regs->data_out);
+       if (value)
+               val |= BIT(offset);
+       else
+               val &= ~BIT(offset);
+
+       writel_relaxed(val, vt8500_chip->base + vt8500_chip->regs->data_out);
+}
+
+static int vt8500_of_xlate(struct gpio_chip *gc,
+                           const struct of_phandle_args *gpiospec, u32 *flags)
+{
+       /* bank if specificed in gpiospec->args[0] */
+       if (flags)
+               *flags = gpiospec->args[2];
+
+       return gpiospec->args[1];
+}
+
+static int vt8500_add_chips(struct platform_device *pdev, void __iomem *base,
+                               const struct vt8500_gpio_data *data)
+{
+       struct vt8500_gpio_chip *vtchip;
+       struct gpio_chip *chip;
+       int i;
+       int pin_cnt = 0;
+
+       vtchip = devm_kzalloc(&pdev->dev,
+                       sizeof(struct vt8500_gpio_chip) * data->num_banks,
+                       GFP_KERNEL);
+       if (!vtchip) {
+               pr_err("%s: failed to allocate chip memory\n", __func__);
+               return -ENOMEM;
+       }
+
+       for (i = 0; i < data->num_banks; i++) {
+               vtchip[i].base = base;
+               vtchip[i].regs = &data->banks[i];
+
+               chip = &vtchip[i].chip;
+
+               chip->of_xlate = vt8500_of_xlate;
+               chip->of_gpio_n_cells = 3;
+               chip->of_node = pdev->dev.of_node;
+
+               chip->request = vt8500_gpio_request;
+               chip->free = vt8500_gpio_free;
+               chip->direction_input = vt8500_gpio_direction_input;
+               chip->direction_output = vt8500_gpio_direction_output;
+               chip->get = vt8500_gpio_get_value;
+               chip->set = vt8500_gpio_set_value;
+               chip->can_sleep = 0;
+               chip->base = pin_cnt;
+               chip->ngpio = data->banks[i].ngpio;
+
+               pin_cnt += data->banks[i].ngpio;
+
+               gpiochip_add(chip);
+       }
+       return 0;
+}
+
+static struct of_device_id vt8500_gpio_dt_ids[] = {
+       { .compatible = "via,vt8500-gpio", .data = &vt8500_data, },
+       { .compatible = "wm,wm8505-gpio", .data = &wm8505_data, },
+       { .compatible = "wm,wm8650-gpio", .data = &wm8650_data, },
+       { /* Sentinel */ },
+};
+
+static int __devinit vt8500_gpio_probe(struct platform_device *pdev)
+{
+       void __iomem *gpio_base;
+       struct device_node *np;
+       const struct of_device_id *of_id =
+                               of_match_device(vt8500_gpio_dt_ids, &pdev->dev);
+
+       if (!of_id) {
+               dev_err(&pdev->dev, "Failed to find gpio controller\n");
+               return -ENODEV;
+       }
+
+       np = pdev->dev.of_node;
+       if (!np) {
+               dev_err(&pdev->dev, "Missing GPIO description in devicetree\n");
+               return -EFAULT;
+       }
+
+       gpio_base = of_iomap(np, 0);
+       if (!gpio_base) {
+               dev_err(&pdev->dev, "Unable to map GPIO registers\n");
+               of_node_put(np);
+               return -ENOMEM;
+       }
+
+       vt8500_add_chips(pdev, gpio_base, of_id->data);
+
+       return 0;
+}
+
+static struct platform_driver vt8500_gpio_driver = {
+       .probe          = vt8500_gpio_probe,
+       .driver         = {
+               .name   = "vt8500-gpio",
+               .owner  = THIS_MODULE,
+               .of_match_table = vt8500_gpio_dt_ids,
+       },
+};
+
+module_platform_driver(vt8500_gpio_driver);
+
+MODULE_DESCRIPTION("VT8500 GPIO Driver");
+MODULE_AUTHOR("Tony Prisk <linux@prisktech.co.nz>");
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(of, vt8500_gpio_dt_ids);