| From 593ee60159355138352679fe7bb7ee4213ea2369 Mon Sep 17 00:00:00 2001 |
| From: =?UTF-8?q?Heiko=20St=C3=BCbner?= <heiko@sntech.de> |
| Date: Mon, 10 Jun 2013 21:40:29 +0200 |
| Subject: pinctrl: add function to parse generic pinconfig properties from a dt |
| node |
| |
| pinconf_generic_parse_dt_config() takes a node as input and generates an |
| array of generic pinconfig values from the properties of this node. |
| |
| As I couldn't find a mechanism to count the number of properties of a node |
| the function uses internally an array to accept one of parameter and copies |
| the real present options to a smaller variable at its end. |
| |
| Signed-off-by: Heiko Stuebner <heiko@sntech.de> |
| Signed-off-by: Linus Walleij <linus.walleij@linaro.org> |
| (cherry picked from commit 7db9af4b6e41be599e0fcd50d687138a5add428c) |
| Signed-off-by: Simon Horman <horms+renesas@verge.net.au> |
| --- |
| .../bindings/pinctrl/pinctrl-bindings.txt | 38 ++++++++++ |
| drivers/pinctrl/pinconf-generic.c | 81 ++++++++++++++++++++++ |
| drivers/pinctrl/pinconf.h | 6 ++ |
| 3 files changed, 125 insertions(+) |
| |
| diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt |
| index c95ea827..ef7cd572 100644 |
| --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt |
| +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt |
| @@ -126,3 +126,41 @@ device; they may be grandchildren, for example. Whether this is legal, and |
| whether there is any interaction between the child and intermediate parent |
| nodes, is again defined entirely by the binding for the individual pin |
| controller device. |
| + |
| +== Using generic pinconfig options == |
| + |
| +Generic pinconfig parameters can be used by defining a separate node containing |
| +the applicable parameters (and optional values), like: |
| + |
| +pcfg_pull_up: pcfg_pull_up { |
| + bias-pull-up; |
| + drive-strength = <20>; |
| +}; |
| + |
| +This node should then be referenced in the appropriate pinctrl node as a phandle |
| +and parsed in the driver using the pinconf_generic_parse_dt_config function. |
| + |
| +Supported configuration parameters are: |
| + |
| +bias-disable - disable any pin bias |
| +bias-high-impedance - high impedance mode ("third-state", "floating") |
| +bias-bus-hold - latch weakly |
| +bias-pull-up - pull up the pin |
| +bias-pull-down - pull down the pin |
| +bias-pull-pin-default - use pin-default pull state |
| +drive-push-pull - drive actively high and low |
| +drive-open-drain - drive with open drain |
| +drive-open-source - drive with open source |
| +drive-strength - sink or source at most X mA |
| +input-schmitt-enable - enable schmitt-trigger mode |
| +input-schmitt-disable - disable schmitt-trigger mode |
| +input-schmitt - run in schmitt-trigger mode with hysteresis X |
| +input-debounce - debounce mode with debound time X |
| +power-source - select power source X |
| +slew-rate - use slew-rate X |
| +low-power-mode - low power mode |
| +output-low - set the pin to output mode with low level |
| +output-high - set the pin to output mode with high level |
| + |
| +More in-depth documentation on these parameters can be found in |
| +<include/linux/pinctrl/pinconfig-generic.h> |
| diff --git a/drivers/pinctrl/pinconf-generic.c b/drivers/pinctrl/pinconf-generic.c |
| index 5810d150..1ddddb95 100644 |
| --- a/drivers/pinctrl/pinconf-generic.c |
| +++ b/drivers/pinctrl/pinconf-generic.c |
| @@ -21,6 +21,7 @@ |
| #include <linux/pinctrl/pinctrl.h> |
| #include <linux/pinctrl/pinconf.h> |
| #include <linux/pinctrl/pinconf-generic.h> |
| +#include <linux/of.h> |
| #include "core.h" |
| #include "pinconf.h" |
| |
| @@ -138,3 +139,83 @@ void pinconf_generic_dump_config(struct pinctrl_dev *pctldev, |
| } |
| EXPORT_SYMBOL_GPL(pinconf_generic_dump_config); |
| #endif |
| + |
| +#ifdef CONFIG_OF |
| +struct pinconf_generic_dt_params { |
| + const char * const property; |
| + enum pin_config_param param; |
| + u32 default_value; |
| +}; |
| + |
| +static struct pinconf_generic_dt_params dt_params[] = { |
| + { "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 }, |
| + { "bias-high-impedance", PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0 }, |
| + { "bias-bus-hold", PIN_CONFIG_BIAS_BUS_HOLD, 0 }, |
| + { "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 0 }, |
| + { "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 0 }, |
| + { "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 0 }, |
| + { "drive-push-pull", PIN_CONFIG_DRIVE_PUSH_PULL, 0 }, |
| + { "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 }, |
| + { "drive-open-source", PIN_CONFIG_DRIVE_OPEN_SOURCE, 0 }, |
| + { "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 }, |
| + { "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 }, |
| + { "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 }, |
| + { "input-schmitt", PIN_CONFIG_INPUT_SCHMITT, 0 }, |
| + { "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 }, |
| + { "power-source", PIN_CONFIG_POWER_SOURCE, 0 }, |
| + { "slew-rate", PIN_CONFIG_SLEW_RATE, 0 }, |
| + { "low-power-mode", PIN_CONFIG_LOW_POWER_MODE, 0 }, |
| + { "output-low", PIN_CONFIG_OUTPUT, 0, }, |
| + { "output-high", PIN_CONFIG_OUTPUT, 1, }, |
| +}; |
| + |
| +/** |
| + * pinconf_generic_parse_dt_config() |
| + * parse the config properties into generic pinconfig values. |
| + * @np: node containing the pinconfig properties |
| + * @configs: array with nconfigs entries containing the generic pinconf values |
| + * @nconfigs: umber of configurations |
| + */ |
| +int pinconf_generic_parse_dt_config(struct device_node *np, |
| + unsigned long **configs, |
| + unsigned int *nconfigs) |
| +{ |
| + unsigned long cfg[ARRAY_SIZE(dt_params)]; |
| + unsigned int ncfg = 0; |
| + int ret; |
| + int i; |
| + u32 val; |
| + |
| + if (!np) |
| + return -EINVAL; |
| + |
| + for (i = 0; i < ARRAY_SIZE(dt_params); i++) { |
| + struct pinconf_generic_dt_params *par = &dt_params[i]; |
| + ret = of_property_read_u32(np, par->property, &val); |
| + |
| + /* property not found */ |
| + if (ret == -EINVAL) |
| + continue; |
| + |
| + /* use default value, when no value is specified */ |
| + if (ret) |
| + val = par->default_value; |
| + |
| + pr_debug("found %s with value %u\n", par->property, val); |
| + cfg[ncfg] = pinconf_to_config_packed(par->param, val); |
| + ncfg++; |
| + } |
| + |
| + /* |
| + * Now limit the number of configs to the real number of |
| + * found properties. |
| + */ |
| + *configs = kzalloc(ncfg * sizeof(unsigned long), GFP_KERNEL); |
| + if (!*configs) |
| + return -ENOMEM; |
| + |
| + memcpy(*configs, &cfg, ncfg * sizeof(unsigned long)); |
| + *nconfigs = ncfg; |
| + return 0; |
| +} |
| +#endif |
| diff --git a/drivers/pinctrl/pinconf.h b/drivers/pinctrl/pinconf.h |
| index 92c72672..a4a5417e 100644 |
| --- a/drivers/pinctrl/pinconf.h |
| +++ b/drivers/pinctrl/pinconf.h |
| @@ -123,3 +123,9 @@ static inline void pinconf_generic_dump_config(struct pinctrl_dev *pctldev, |
| return; |
| } |
| #endif |
| + |
| +#if defined(CONFIG_GENERIC_PINCONF) && defined(CONFIG_OF) |
| +int pinconf_generic_parse_dt_config(struct device_node *np, |
| + unsigned long **configs, |
| + unsigned int *nconfigs); |
| +#endif |
| -- |
| 1.8.4.3.gca3854a |
| |