[U-Boot] [PATCH v6 3/4] EXYNOS5: GPIO: Support GPIO Command for EXYNOS5

Akshay Saraswat
2014-04-12T09:43:31Z

From: Rajeshwari Shinde <rajeshwari.s@samsung.com>

This patch adds support for name to gpio conversion in s5p_gpio
to enable gpio command EXYNOS 5250 & 5420.
Function has been added to asm/gpio.h to decode the
input gpio name to gpio number.

Example: SMDK5420 # gpio set gpa00

Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
Signed-off-by: Akshay Saraswat <akshay.s@samsung.com>
---
arch/arm/include/asm/arch-exynos/gpio.h | 28 +++++++++
drivers/gpio/s5p_gpio.c | 105 ++++++++++++++++++++++++++++++++
2 files changed, 133 insertions(+)

diff --git a/arch/arm/include/asm/arch-exynos/gpio.h b/arch/arm/include/asm/arch-exynos/gpio.h
index 697e6f3..3736a22 100644
--- a/arch/arm/include/asm/arch-exynos/gpio.h
+++ b/arch/arm/include/asm/arch-exynos/gpio.h
@@ -1038,6 +1038,34 @@ static inline unsigned int get_bank_num(void)
}
}

+/*
+ * This structure helps mapping symbolic GPIO names into indices from
+ * exynos5_gpio_pin/exynos5420_gpio_pin enums.
+ *
+ * By convention, symbolic GPIO name is defined as follows:
+ *
+ * g[p]<bank><set><bit>, where
+ * p is optional
+ * <bank> - a single character bank name, as defined by the SOC
+ * <set> - a single digit set number
+ * <bit> - bit number within the set (in 0..7 range).
+ *
+ * <set><bit> essentially form an octal number of the GPIO pin within the bank
+ * space. On the 5420 architecture some banks' sets do not start not from zero
+ * ('d' starts from 1 and 'j' starts from 4). To compensate for that and
+ * maintain flat number space withoout holes, those banks use offsets to be
+ * deducted from the pin number.
+ */
+struct gpio_name_num_table {
+ char bank; /* bank name symbol */
+ u8 bank_size; /* total number of pins in the bank */
+ char bank_offset; /* offset of the first bank's pin */
+ unsigned int base; /* index of the first bank's pin in the enum */
+};
+
+int s5p_name_to_gpio(const char *name);
+#define name_to_gpio(n) s5p_name_to_gpio(n)
+
void gpio_cfg_pin(int gpio, int cfg);
void gpio_set_pull(int gpio, int mode);
void gpio_set_drv(int gpio, int mode);
diff --git a/drivers/gpio/s5p_gpio.c b/drivers/gpio/s5p_gpio.c
index b1b6fbe..9a80b0c 100644
--- a/drivers/gpio/s5p_gpio.c
+++ b/drivers/gpio/s5p_gpio.c
@@ -28,6 +28,111 @@
#define RATE_MASK(x) (0x1 << (x + 16))
#define RATE_SET(x) (0x1 << (x + 16))

+#define GPIO_ENTRY(name, base, top, offset) { name, top - base, offset, base }
+static const struct gpio_name_num_table exynos5_gpio_table[] = {
+ GPIO_ENTRY('a', EXYNOS5_GPIO_A00, EXYNOS5_GPIO_B00, 0),
+ GPIO_ENTRY('b', EXYNOS5_GPIO_B00, EXYNOS5_GPIO_C00, 0),
+ GPIO_ENTRY('c', EXYNOS5_GPIO_C00, EXYNOS5_GPIO_D00, 0),
+ GPIO_ENTRY('d', EXYNOS5_GPIO_D00, EXYNOS5_GPIO_Y00, 0),
+ GPIO_ENTRY('y', EXYNOS5_GPIO_Y00, EXYNOS5_GPIO_C40, 0),
+ GPIO_ENTRY('x', EXYNOS5_GPIO_X00, EXYNOS5_GPIO_E00, 0),
+ GPIO_ENTRY('e', EXYNOS5_GPIO_E00, EXYNOS5_GPIO_F00, 0),
+ GPIO_ENTRY('f', EXYNOS5_GPIO_F00, EXYNOS5_GPIO_G00, 0),
+ GPIO_ENTRY('g', EXYNOS5_GPIO_G00, EXYNOS5_GPIO_H00, 0),
+ GPIO_ENTRY('h', EXYNOS5_GPIO_H00, EXYNOS5_GPIO_V00, 0),
+ GPIO_ENTRY('v', EXYNOS5_GPIO_V00, EXYNOS5_GPIO_Z0, 0),
+ GPIO_ENTRY('z', EXYNOS5_GPIO_Z0, EXYNOS5_GPIO_MAX_PORT, 0),
+ { 0 }
+};
+
+static const struct gpio_name_num_table exynos5420_gpio_table[] = {
+ GPIO_ENTRY('a', EXYNOS5420_GPIO_A00, EXYNOS5420_GPIO_B00, 0),
+ GPIO_ENTRY('b', EXYNOS5420_GPIO_B00, EXYNOS5420_GPIO_H00, 0),
+ GPIO_ENTRY('h', EXYNOS5420_GPIO_H00, EXYNOS5420_GPIO_Y70, 0),
+ GPIO_ENTRY('x', EXYNOS5420_GPIO_X00, EXYNOS5420_GPIO_C00, 0),
+ GPIO_ENTRY('c', EXYNOS5420_GPIO_C00, EXYNOS5420_GPIO_D10, 0),
+ GPIO_ENTRY('d', EXYNOS5420_GPIO_D10, EXYNOS5420_GPIO_Y00, 010),
+ GPIO_ENTRY('y', EXYNOS5420_GPIO_Y00, EXYNOS5420_GPIO_E00, 0),
+ GPIO_ENTRY('e', EXYNOS5420_GPIO_E00, EXYNOS5420_GPIO_F00, 0),
+ GPIO_ENTRY('f', EXYNOS5420_GPIO_F00, EXYNOS5420_GPIO_G00, 0),
+ GPIO_ENTRY('g', EXYNOS5420_GPIO_G00, EXYNOS5420_GPIO_J40, 0),
+ GPIO_ENTRY('j', EXYNOS5420_GPIO_J40, EXYNOS5420_GPIO_Z0, 040),
+ GPIO_ENTRY('z', EXYNOS5420_GPIO_Z0, EXYNOS5420_GPIO_MAX_PORT, 0),
+ { 0 }
+};
+
+int s5p_name_to_gpio(const char *name)
+{
+ unsigned num, irregular_set_number, irregular_bank_base;
+ const struct gpio_name_num_table *tabp;
+ char this_bank, bank_name, irregular_bank_name;
+ char *endp;
+
+ /*
+ * The gpio name starts with either 'g' ot 'gp' followed by the bank
+ * name character. Skip one or two characters depending on the prefix.
+ */
+ if (name[1] == 'p')
+ name += 2;
+ else
+ name++;
+ bank_name = *name++;
+ if (!*name)
+ return -1; /* At least one digit is required/expected. */
+
+ /*
+ * On both exynos5 and exynos5420 architectures there is a bank of
+ * GPIOs which does not fall into the regular address pattern. Those
+ * banks are c4 on Exynos5 and y7 on Exynos5420. The rest of the below
+ * assignments help to handle these irregularities.
+ */
+ if (proid_is_exynos5420()) {
+ tabp = exynos5420_gpio_table;
+ irregular_bank_name = 'y';
+ irregular_set_number = '7';
+ irregular_bank_base = EXYNOS5420_GPIO_Y70;
+ } else {
+ tabp = exynos5_gpio_table;
+ irregular_bank_name = 'c';
+ irregular_set_number = '4';
+ irregular_bank_base = EXYNOS5_GPIO_C40;
+ }
+
+ this_bank = tabp->bank;
+ do {
+ if (bank_name == this_bank) {
+ unsigned pin_index; /* pin number within the bank */
+ if ((bank_name == irregular_bank_name) &&
+ (name[0] == irregular_set_number)) {
+ pin_index = name[1] - '0';
+ /* Irregular sets have 8 pins. */
+ if (pin_index >= GPIO_PER_BANK)
+ return -1;
+ num = irregular_bank_base + pin_index;
+ } else {
+ pin_index = simple_strtoul(name, &endp, 8);
+ pin_index -= tabp->bank_offset;
+ /*
+ * Sanity check: bunk 'z' has no set number,
+ * for all other banks there must be exactly
+ * two octal digits, and the resulting number
+ * should not exceed the number of pins in the
+ * bank.
+ */
+ if (((bank_name != 'z') && !name[1]) ||
+ *endp ||
+ (pin_index >= tabp->bank_size))
+ return -1;
+ num = tabp->base + pin_index;
+ }
+ return num;
+ }
+ this_bank = (++tabp)->bank;
+ } while (this_bank);
+
+ return -1;
+}
+
void s5p_gpio_cfg_pin(struct s5p_gpio_bank *bank, int gpio, int cfg)
{
unsigned int value;
--
1.8.3.2