--- /dev/null
+/* 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);
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