pinctrl: enhance mapping table to support pin config operations

The pinctrl mapping table can now contain entries to:
* Set the mux function of a pin group
* Apply a set of pin config options to a pin or a group

This allows pinctrl_select_state() to apply pin configs settings as well
as mux settings.

v3: Fix find_pinctrl() to iterate over the correct list.
   s/_MUX_CONFIGS_/_CONFIGS_/ in mapping table macros.
   Fix documentation to use correct mapping table macro.
v2: Added numerous extra PIN_MAP_*() special-case macros.
   Fixed kerneldoc typo. Delete pinctrl_get_pin_id() and
   replace it with pin_get_from_name(). Various minor fixes.
   Updates due to rebase.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/pinctrl.txt

@@ -206,14 +206,21 @@ using a certain resistor value - pull up and pull down - so that the pin has a
 stable value when nothing is driving the rail it is connected to, or when it's
 unconnected.
 
-For example, a platform may do this:
+Pin configuration can be programmed either using the explicit APIs described
+immediately below, or by adding configuration entries into the mapping table;
+see section "Board/machine configuration" below.
+
+For example, a platform may do the following to pull up a pin to VDD:
 
 #include <linux/pinctrl/consumer.h>
 
 ret = pin_config_set("foo-dev", "FOO_GPIO_PIN", PLATFORM_X_PULL_UP);
 
-To pull up a pin to VDD. The pin configuration driver implements callbacks for
-changing pin configuration in the pin controller ops like this:
+The format and meaning of the configuration parameter, PLATFORM_X_PULL_UP
+above, is entirely defined by the pin controller driver.
+
+The pin configuration driver implements callbacks for changing pin
+configuration in the pin controller ops like this:
 
 #include <linux/pinctrl/pinctrl.h>
 #include <linux/pinctrl/pinconf.h>
@@ -765,38 +772,41 @@ obtain the function "gpioN" where "N" is the global GPIO pin number if no
 special GPIO-handler is registered.
 
 
-Pinmux board/machine configuration
+Board/machine configuration
 ==================================
 
 Boards and machines define how a certain complete running system is put
 together, including how GPIOs and devices are muxed, how regulators are
 constrained and how the clock tree looks. Of course pinmux settings are also
 part of this.
 
-A pinmux config for a machine looks pretty much like a simple regulator
-configuration, so for the example array above we want to enable i2c and
-spi on the second function mapping:
+A pin controller configuration for a machine looks pretty much like a simple
+regulator configuration, so for the example array above we want to enable i2c
+and spi on the second function mapping:
 
 #include <linux/pinctrl/machine.h>
 
 static const struct pinctrl_map __initdata mapping[] = {
 	{
 		.dev_name = "foo-spi.0",
 		.name = PINCTRL_STATE_DEFAULT,
+		.type = PIN_MAP_TYPE_MUX_GROUP,
 		.ctrl_dev_name = "pinctrl-foo",
-		.function = "spi0",
+		.data.mux.function = "spi0",
 	},
 	{
 		.dev_name = "foo-i2c.0",
 		.name = PINCTRL_STATE_DEFAULT,
+		.type = PIN_MAP_TYPE_MUX_GROUP,
 		.ctrl_dev_name = "pinctrl-foo",
-		.function = "i2c0",
+		.data.mux.function = "i2c0",
 	},
 	{
 		.dev_name = "foo-mmc.0",
 		.name = PINCTRL_STATE_DEFAULT,
+		.type = PIN_MAP_TYPE_MUX_GROUP,
 		.ctrl_dev_name = "pinctrl-foo",
-		.function = "mmc0",
+		.data.mux.function = "mmc0",
 	},
 };
 
@@ -817,7 +827,40 @@ it even more compact which assumes you want to use pinctrl-foo and position
 0 for mapping, for example:
 
 static struct pinctrl_map __initdata mapping[] = {
-	PIN_MAP(PINCTRL_STATE_DEFAULT, "pinctrl-foo", "i2c0", "foo-i2c.0"),
+	PIN_MAP_MUX_GROUP("foo-i2c.o", PINCTRL_STATE_DEFAULT, "pinctrl-foo", NULL, "i2c0"),
+};
+
+The mapping table may also contain pin configuration entries. It's common for
+each pin/group to have a number of configuration entries that affect it, so
+the table entries for configuration reference an array of config parameters
+and values. An example using the convenience macros is shown below:
+
+static unsigned long i2c_grp_configs[] = {
+	FOO_PIN_DRIVEN,
+	FOO_PIN_PULLUP,
+};
+
+static unsigned long i2c_pin_configs[] = {
+	FOO_OPEN_COLLECTOR,
+	FOO_SLEW_RATE_SLOW,
+};
+
+static struct pinctrl_map __initdata mapping[] = {
+	PIN_MAP_MUX_GROUP("foo-i2c.0", PINCTRL_STATE_DEFAULT, "pinctrl-foo", "i2c0", "i2c0"),
+	PIN_MAP_MUX_CONFIGS_GROUP("foo-i2c.0", PINCTRL_STATE_DEFAULT, "pinctrl-foo", "i2c0", i2c_grp_configs),
+	PIN_MAP_MUX_CONFIGS_PIN("foo-i2c.0", PINCTRL_STATE_DEFAULT, "pinctrl-foo", "i2c0scl", i2c_pin_configs),
+	PIN_MAP_MUX_CONFIGS_PIN("foo-i2c.0", PINCTRL_STATE_DEFAULT, "pinctrl-foo", "i2c0sda", i2c_pin_configs),
+};
+
+Finally, some devices expect the mapping table to contain certain specific
+named states. When running on hardware that doesn't need any pin controller
+configuration, the mapping table must still contain those named states, in
+order to explicitly indicate that the states were provided and intended to
+be empty. Table entry macro PIN_MAP_DUMMY_STATE serves the purpose of defining
+a named state without causing any pin controller to be programmed:
+
+static struct pinctrl_map __initdata mapping[] = {
+	PIN_MAP_DUMMY_STATE("foo-i2c.0", PINCTRL_STATE_DEFAULT),
 };
 
 
@@ -831,13 +874,15 @@ As it is possible to map a function to different groups of pins an optional
 {
 	.dev_name = "foo-spi.0",
 	.name = "spi0-pos-A",
+	.type = PIN_MAP_TYPE_MUX_GROUP,
 	.ctrl_dev_name = "pinctrl-foo",
 	.function = "spi0",
 	.group = "spi0_0_grp",
 },
 {
 	.dev_name = "foo-spi.0",
 	.name = "spi0-pos-B",
+	.type = PIN_MAP_TYPE_MUX_GROUP,
 	.ctrl_dev_name = "pinctrl-foo",
 	.function = "spi0",
 	.group = "spi0_1_grp",
@@ -857,41 +902,47 @@ case), we define a mapping like this:
 {
 	.dev_name = "foo-mmc.0",
 	.name = "2bit"
+	.type = PIN_MAP_TYPE_MUX_GROUP,
 	.ctrl_dev_name = "pinctrl-foo",
 	.function = "mmc0",
 	.group = "mmc0_1_grp",
 },
 {
 	.dev_name = "foo-mmc.0",
 	.name = "4bit"
+	.type = PIN_MAP_TYPE_MUX_GROUP,
 	.ctrl_dev_name = "pinctrl-foo",
 	.function = "mmc0",
 	.group = "mmc0_1_grp",
 },
 {
 	.dev_name = "foo-mmc.0",
 	.name = "4bit"
+	.type = PIN_MAP_TYPE_MUX_GROUP,
 	.ctrl_dev_name = "pinctrl-foo",
 	.function = "mmc0",
 	.group = "mmc0_2_grp",
 },
 {
 	.dev_name = "foo-mmc.0",
 	.name = "8bit"
+	.type = PIN_MAP_TYPE_MUX_GROUP,
 	.ctrl_dev_name = "pinctrl-foo",
 	.function = "mmc0",
 	.group = "mmc0_1_grp",
 },
 {
 	.dev_name = "foo-mmc.0",
 	.name = "8bit"
+	.type = PIN_MAP_TYPE_MUX_GROUP,
 	.ctrl_dev_name = "pinctrl-foo",
 	.function = "mmc0",
 	.group = "mmc0_2_grp",
 },
 {
 	.dev_name = "foo-mmc.0",
 	.name = "8bit"
+	.type = PIN_MAP_TYPE_MUX_GROUP,
 	.ctrl_dev_name = "pinctrl-foo",
 	.function = "mmc0",
 	.group = "mmc0_3_grp",
@@ -1014,6 +1065,7 @@ to the pin controller device name, and the state name is PINCTRL_STATE_DEFAULT.
 {
 	.dev_name = "pinctrl-foo",
 	.name = PINCTRL_STATE_DEFAULT,
+	.type = PIN_MAP_TYPE_MUX_GROUP,
 	.ctrl_dev_name = "pinctrl-foo",
 	.function = "power_func",
 },
@@ -1022,7 +1074,7 @@ Since it may be common to request the core to hog a few always-applicable
 mux settings on the primary pin controller, there is a convenience macro for
 this:
 
-PIN_MAP_SYS_HOG("pinctrl-foo", "power_func")
+PIN_MAP_MUX_GROUP_HOG_DEFAULT("pinctrl-foo", NULL /* group */, "power_func")
 
 This gives the exact same result as the above construction.
 

arch/arm/mach-u300/core.c

@@ -1608,13 +1608,13 @@ static struct platform_device dma_device = {
 /* Pinmux settings */
 static struct pinctrl_map __initdata u300_pinmux_map[] = {
 	/* anonymous maps for chip power and EMIFs */
-	PIN_MAP_SYS_HOG("pinctrl-u300", "power"),
-	PIN_MAP_SYS_HOG("pinctrl-u300", "emif0"),
-	PIN_MAP_SYS_HOG("pinctrl-u300", "emif1"),
+	PIN_MAP_MUX_GROUP_HOG_DEFAULT("pinctrl-u300", NULL, "power"),
+	PIN_MAP_MUX_GROUP_HOG_DEFAULT("pinctrl-u300", NULL, "emif0"),
+	PIN_MAP_MUX_GROUP_HOG_DEFAULT("pinctrl-u300", NULL, "emif1"),
 	/* per-device maps for MMC/SD, SPI and UART */
-	PIN_MAP(PINCTRL_STATE_DEFAULT, "pinctrl-u300", "mmc0", "mmci"),
-	PIN_MAP(PINCTRL_STATE_DEFAULT, "pinctrl-u300", "spi0", "pl022"),
-	PIN_MAP(PINCTRL_STATE_DEFAULT, "pinctrl-u300", "uart0", "uart0"),
+	PIN_MAP_MUX_GROUP_DEFAULT("mmci",  "pinctrl-u300", NULL, "mmc0"),
+	PIN_MAP_MUX_GROUP_DEFAULT("pl022", "pinctrl-u300", NULL, "spi0"),
+	PIN_MAP_MUX_GROUP_DEFAULT("uart0", "pinctrl-u300", NULL, "uart0"),
 };
 
 struct u300_mux_hog {