Hi Masahiro,
On 21 July 2015 at 21:46, Simon Glass sjg@chromium.org wrote:
Hi Masahiro,
On 21 July 2015 at 12:19, Masahiro Yamada yamada.masahiro@socionext.com wrote:
Hi Simon,
2015-07-18 23:36 GMT+09:00 Simon Glass sjg@chromium.org:
Hi Masahiro,
On 13 July 2015 at 02:29, Masahiro Yamada yamada.masahiro@socionext.com wrote:
This GPIO controller device is used on UniPhier SoCs.
Signed-off-by: Masahiro Yamada yamada.masahiro@socionext.com
drivers/gpio/Kconfig | 6 ++ drivers/gpio/Makefile | 1 + drivers/gpio/gpio-uniphier.c | 186 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 193 insertions(+) create mode 100644 drivers/gpio/gpio-uniphier.c
[snip]
+static void uniphier_gpio_offset_write(struct udevice *dev, unsigned offset,
unsigned reg_type, int value)+{
struct uniphier_gpio_priv *priv = dev_get_priv(dev);unsigned bank = offset / UNIPHIER_GPIO_PORTS_PER_BANK;unsigned bit = offset % UNIPHIER_GPIO_PORTS_PER_BANK;unsigned reg;u32 tmp;reg = uniphier_gpio_bank_to_reg(bank, reg_type);I think what you want is a struct gpio_bank or similar, and then store the bank pointer in the device. We should use C struct access for I/O.
Why? Rationale please?
When I see drivers/gpio/gpio-tegra.c in Linux, I only see macros
#define GPIO_CNF(x) (GPIO_REG(x) + 0x00) #define GPIO_OE(x) (GPIO_REG(x) + 0x10) #define GPIO_OUT(x) (GPIO_REG(x) + 0X20) #define GPIO_IN(x) (GPIO_REG(x) + 0x30) #define GPIO_INT_STA(x) (GPIO_REG(x) + 0x40) #define GPIO_INT_ENB(x) (GPIO_REG(x) + 0x50) #define GPIO_INT_LVL(x) (GPIO_REG(x) + 0x60) #define GPIO_INT_CLR(x) (GPIO_REG(x) + 0x70)
Actually, looks like macros are more often used in Linux for accessing I/O.
Right, but U-Boot uses structures normally.
I am negative about using C struct for this purpose because:
- C struct is not flexible because we can not change the register stride with the "reg-shift" property.
Do you need to? To me that would be unusual hardware.
Or are you saying that on Uniphier each SoC uses a different register size and so the driver has to handle this? If so then I agree what you have is best. I noticed something similar in your pinctrl series.
[snip]
Regards, Simon