Re: [PATCH v1 1/2] pinctrl: rockchip：Add input schmitt support

[David.Wu]

Hi Heiko,

在 2017/2/24 0:51, Heiko Stuebner 写道:
Hi David,
Am Dienstag, 14. Februar 2017, 18:35:40 CET schrieb David Wu:
From: "david.wu" <david...@rock-chips.com>

 struct rockchip_pin_config {
@@ -1355,6 +1358,53 @@ static int rockchip_set_pull(struct rockchip_pin_bank
*bank, return ret;
 }

+static int rockchip_get_schmitt(struct rockchip_pin_bank *bank, int
pin_num) +{
+       struct rockchip_pinctrl *info = bank->drvdata;
+       struct rockchip_pin_ctrl *ctrl = info->ctrl;
+       struct regmap *regmap;
+       int reg, ret;
+       u8 bit;
+       u32 data;
+
+       ctrl->schmitt_calc_reg(bank, pin_num, &regmap, &reg, &bit);

we might want to have and check an actual return value here.
On things like the rk3288 only some special pins have these schmitt triggers
it seems, so we might want to abort if something tries to access an
unsupported one.

Thanks, i forget to check the return value.

+
+       ret = regmap_read(regmap, reg, &data);
+       if (ret)
+               return ret;
+
+       data >>= bit;
+       return data & 0x1;

The mask seems to also be variable, for example on the rk3399 there seem to be
multiple "levels" for at least gpio2. So your calc-callback might want to also
set the right mask.

To the multiple "levels", i think we can use the 
"PIN_CONFIG_INPUT_SCHMITT" pin config, which described at pinconf-generic.h.

 * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in
 *      schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis,
 *      the threshold value is given on a custom format as argument when
 *      setting pins to this mode.


Otherwise looks good.


Heiko