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authorLinus Torvalds <torvalds@linux-foundation.org>2014-01-21 10:14:10 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-01-21 10:14:10 -0800
commita547df99aad777c1807e23991fa2471693c0e4cc (patch)
tree8e0a198648483580c9a7aa40efa4927c282fa4b1 /Documentation
parent8e5096607280d4e103389bfe8f8b7decbf538ff6 (diff)
parentfa8cf57c923e86a693a85aff1df579245a27cbb3 (diff)
Merge tag 'pinctrl-v3.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull bulk pin control changes from Linus Walleij: "This has been queued and tested for a while. Lots of action here, like in the GPIO tree, embedded stuff like this is really hot now it seems. Details in the signed tag. I'm especially happy about the Qualcomm driver as it is used in such a huge subset of mobile handsets out there, and these platforms in general need better upstream support - New driver for the Qualcomm TLMM pin controller and its msm8x74 subdriver. - New driver for the Broadcom Capri BCM281xx SoC. - New subdriver for the imx25 pin controller. - New subdriver for the Tegra124 pin controller. - Lock GPIO lines as IRQs for select combined pin control and GPIO drivers for baytrail and sirf. - Some semi-big refactorings and extenstions to the sirf driver. - Lots of patching, cleanup and fixing in the Renesas "PFC" driver and associated subdrivers as usual. It is settling down a little bit now it seems. - Minor fixes and incremental updates here and there as usual" * tag 'pinctrl-v3.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (72 commits) pinctrl: sunxi: Honor GPIO output initial vaules pinctrl: capri: add dependency on OF ARM: bcm11351: Enable pinctrl for Broadcom Capri SoCs ARM: pinctrl: Add Broadcom Capri pinctrl driver pinctrl: Add pinctrl binding for Broadcom Capri SoCs pinctrl: Add void * to pinctrl_pin_desc pinctrl: st: Fix a typo in probe pinctrl: Fix some typos and grammar issues in the documentation pinctrl: sirf: lock IRQs when starting them pinctrl: sirf: put gpio interrupt pin into input status automatically pinctrl: sirf: use only one irq_domain for the whole device node pinctrl: single: fix infinite loop caused by bad mask pinctrl: single: fix pcs_disable with bits_per_mux pinctrl: single: fix DT bindings documentation pinctrl: as3722: Set pin to output mode for some function pinctrl: sirf: add pin group for USP0 with only RX or TX frame sync pinctrl: sirf: fix the pins of sdmmc5 connected with TriG pinctrl: sirf: add lost usp1_uart_nostreamctrl group for atlas6 pinctrl: sunxi: Add Allwinner A20 clock output pin functions pinctrl/lantiq: fix typo ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/pinctrl/brcm,capri-pinctrl.txt461
-rw-r--r--Documentation/devicetree/bindings/pinctrl/fsl,imx25-pinctrl.txt23
-rw-r--r--Documentation/devicetree/bindings/pinctrl/fsl,imx27-pinctrl.txt22
-rw-r--r--Documentation/devicetree/bindings/pinctrl/nvidia,tegra124-pinmux.txt144
-rw-r--r--Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt3
-rw-r--r--Documentation/devicetree/bindings/pinctrl/pinctrl-single.txt2
-rw-r--r--Documentation/devicetree/bindings/pinctrl/qcom,msm8974-pinctrl.txt92
-rw-r--r--Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt14
-rw-r--r--Documentation/pinctrl.txt43
9 files changed, 781 insertions, 23 deletions
diff --git a/Documentation/devicetree/bindings/pinctrl/brcm,capri-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/brcm,capri-pinctrl.txt
new file mode 100644
index 00000000000..9e9e9ef9f85
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/brcm,capri-pinctrl.txt
@@ -0,0 +1,461 @@
+Broadcom Capri Pin Controller
+
+This is a pin controller for the Broadcom BCM281xx SoC family, which includes
+BCM11130, BCM11140, BCM11351, BCM28145, and BCM28155 SoCs.
+
+=== Pin Controller Node ===
+
+Required Properties:
+
+- compatible: Must be "brcm,capri-pinctrl".
+- reg: Base address of the PAD Controller register block and the size
+ of the block.
+
+For example, the following is the bare minimum node:
+
+ pinctrl@35004800 {
+ compatible = "brcm,capri-pinctrl";
+ reg = <0x35004800 0x430>;
+ };
+
+As a pin controller device, in addition to the required properties, this node
+should also contain the pin configuration nodes that client devices reference,
+if any.
+
+=== Pin Configuration Node ===
+
+Each pin configuration node is a sub-node of the pin controller node and is a
+container of an arbitrary number of subnodes, called pin group nodes in this
+document.
+
+Please refer to the pinctrl-bindings.txt in this directory for details of the
+common pinctrl bindings used by client devices, including the definition of a
+"pin configuration node".
+
+=== Pin Group Node ===
+
+A pin group node specifies the desired pin mux and/or pin configuration for an
+arbitrary number of pins. The name of the pin group node is optional and not
+used.
+
+A pin group node only affects the properties specified in the node, and has no
+effect on any properties that are omitted.
+
+The pin group node accepts a subset of the generic pin config properties. For
+details generic pin config properties, please refer to pinctrl-bindings.txt
+and <include/linux/pinctrl/pinconfig-generic.h>.
+
+Each pin controlled by this pin controller belong to one of three types:
+Standard, I2C, and HDMI. Each type accepts a different set of pin config
+properties. A list of pins and their types is provided below.
+
+Required Properties (applicable to all pins):
+
+- pins: Multiple strings. Specifies the name(s) of one or more pins to
+ be configured by this node.
+
+Optional Properties (for standard pins):
+
+- function: String. Specifies the pin mux selection. Values
+ must be one of: "alt1", "alt2", "alt3", "alt4"
+- input-schmitt-enable: No arguments. Enable schmitt-trigger mode.
+- input-schmitt-disable: No arguments. Disable schmitt-trigger mode.
+- bias-pull-up: No arguments. Pull up on pin.
+- bias-pull-down: No arguments. Pull down on pin.
+- bias-disable: No arguments. Disable pin bias.
+- slew-rate: Integer. Meaning depends on configured pin mux:
+ *_SCL or *_SDA:
+ 0: Standard(100kbps)& Fast(400kbps) mode
+ 1: Highspeed (3.4Mbps) mode
+ IC_DM or IC_DP:
+ 0: normal slew rate
+ 1: fast slew rate
+ Otherwise:
+ 0: fast slew rate
+ 1: normal slew rate
+- input-enable: No arguements. Enable input (does not affect
+ output.)
+- input-disable: No arguements. Disable input (does not affect
+ output.)
+- drive-strength: Integer. Drive strength in mA. Valid values are
+ 2, 4, 6, 8, 10, 12, 14, 16 mA.
+
+Optional Properties (for I2C pins):
+
+- function: String. Specifies the pin mux selection. Values
+ must be one of: "alt1", "alt2", "alt3", "alt4"
+- bias-pull-up: Integer. Pull up strength in Ohm. There are 3
+ pull-up resisitors (1.2k, 1.8k, 2.7k) available
+ in parallel for I2C pins, so the valid values
+ are: 568, 720, 831, 1080, 1200, 1800, 2700 Ohm.
+- bias-disable: No arguments. Disable pin bias.
+- slew-rate: Integer. Meaning depends on configured pin mux:
+ *_SCL or *_SDA:
+ 0: Standard(100kbps)& Fast(400kbps) mode
+ 1: Highspeed (3.4Mbps) mode
+ IC_DM or IC_DP:
+ 0: normal slew rate
+ 1: fast slew rate
+ Otherwise:
+ 0: fast slew rate
+ 1: normal slew rate
+- input-enable: No arguements. Enable input (does not affect
+ output.)
+- input-disable: No arguements. Disable input (does not affect
+ output.)
+
+Optional Properties (for HDMI pins):
+
+- function: String. Specifies the pin mux selection. Values
+ must be one of: "alt1", "alt2", "alt3", "alt4"
+- slew-rate: Integer. Controls slew rate.
+ 0: Standard(100kbps)& Fast(400kbps) mode
+ 1: Highspeed (3.4Mbps) mode
+- input-enable: No arguements. Enable input (does not affect
+ output.)
+- input-disable: No arguements. Disable input (does not affect
+ output.)
+
+Example:
+// pin controller node
+pinctrl@35004800 {
+ compatible = "brcm,capri-pinctrl";
+ reg = <0x35004800 0x430>;
+
+ // pin configuration node
+ dev_a_default: dev_a_active {
+ //group node defining 1 standard pin
+ grp_1 {
+ pins = "std_pin1";
+ function = "alt1";
+ input-schmitt-enable;
+ bias-disable;
+ slew-rate = <1>;
+ drive-strength = <4>;
+ };
+
+ // group node defining 2 I2C pins
+ grp_2 {
+ pins = "i2c_pin1", "i2c_pin2";
+ function = "alt2";
+ bias-pull-up = <720>;
+ input-enable;
+ };
+
+ // group node defining 2 HDMI pins
+ grp_3 {
+ pins = "hdmi_pin1", "hdmi_pin2";
+ function = "alt3";
+ slew-rate = <1>;
+ };
+
+ // other pin group nodes
+ ...
+ };
+
+ // other pin configuration nodes
+ ...
+};
+
+In the example above, "dev_a_active" is a pin configuration node with a number
+of sub-nodes. In the pin group node "grp_1", one pin, "std_pin1", is defined in
+the "pins" property. Thus, the remaining properties in the "grp_1" node applies
+only to this pin, including the following settings:
+ - setting pinmux to "alt1"
+ - enabling schmitt-trigger (hystersis) mode
+ - disabling pin bias
+ - setting the slew-rate to 1
+ - setting the drive strength to 4 mA
+Note that neither "input-enable" nor "input-disable" was specified - the pinctrl
+subsystem will therefore leave this property unchanged from whatever state it
+was in before applying these changes.
+
+The "pins" property in the pin group node "grp_2" specifies two pins -
+"i2c_pin1" and "i2c_pin2"; the remaining properties in this pin group node,
+therefore, applies to both of these pins. The properties include:
+ - setting pinmux to "alt2"
+ - setting pull-up resistance to 720 Ohm (ie. enabling 1.2k and 1.8k resistors
+ in parallel)
+ - enabling both pins' input
+"slew-rate" is not specified in this pin group node, so the slew-rate for these
+pins are left as-is.
+
+Finally, "grp_3" defines two HDMI pins. The following properties are applied to
+both pins:
+ - setting pinmux to "alt3"
+ - setting slew-rate to 1; for HDMI pins, this corresponds to the 3.4 Mbps
+ Highspeed mode
+The input is neither enabled or disabled, and is left untouched.
+
+=== Pin Names and Type ===
+
+The following are valid pin names and their pin types:
+
+ "adcsync", Standard
+ "bat_rm", Standard
+ "bsc1_scl", I2C
+ "bsc1_sda", I2C
+ "bsc2_scl", I2C
+ "bsc2_sda", I2C
+ "classgpwr", Standard
+ "clk_cx8", Standard
+ "clkout_0", Standard
+ "clkout_1", Standard
+ "clkout_2", Standard
+ "clkout_3", Standard
+ "clkreq_in_0", Standard
+ "clkreq_in_1", Standard
+ "cws_sys_req1", Standard
+ "cws_sys_req2", Standard
+ "cws_sys_req3", Standard
+ "digmic1_clk", Standard
+ "digmic1_dq", Standard
+ "digmic2_clk", Standard
+ "digmic2_dq", Standard
+ "gpen13", Standard
+ "gpen14", Standard
+ "gpen15", Standard
+ "gpio00", Standard
+ "gpio01", Standard
+ "gpio02", Standard
+ "gpio03", Standard
+ "gpio04", Standard
+ "gpio05", Standard
+ "gpio06", Standard
+ "gpio07", Standard
+ "gpio08", Standard
+ "gpio09", Standard
+ "gpio10", Standard
+ "gpio11", Standard
+ "gpio12", Standard
+ "gpio13", Standard
+ "gpio14", Standard
+ "gps_pablank", Standard
+ "gps_tmark", Standard
+ "hdmi_scl", HDMI
+ "hdmi_sda", HDMI
+ "ic_dm", Standard
+ "ic_dp", Standard
+ "kp_col_ip_0", Standard
+ "kp_col_ip_1", Standard
+ "kp_col_ip_2", Standard
+ "kp_col_ip_3", Standard
+ "kp_row_op_0", Standard
+ "kp_row_op_1", Standard
+ "kp_row_op_2", Standard
+ "kp_row_op_3", Standard
+ "lcd_b_0", Standard
+ "lcd_b_1", Standard
+ "lcd_b_2", Standard
+ "lcd_b_3", Standard
+ "lcd_b_4", Standard
+ "lcd_b_5", Standard
+ "lcd_b_6", Standard
+ "lcd_b_7", Standard
+ "lcd_g_0", Standard
+ "lcd_g_1", Standard
+ "lcd_g_2", Standard
+ "lcd_g_3", Standard
+ "lcd_g_4", Standard
+ "lcd_g_5", Standard
+ "lcd_g_6", Standard
+ "lcd_g_7", Standard
+ "lcd_hsync", Standard
+ "lcd_oe", Standard
+ "lcd_pclk", Standard
+ "lcd_r_0", Standard
+ "lcd_r_1", Standard
+ "lcd_r_2", Standard
+ "lcd_r_3", Standard
+ "lcd_r_4", Standard
+ "lcd_r_5", Standard
+ "lcd_r_6", Standard
+ "lcd_r_7", Standard
+ "lcd_vsync", Standard
+ "mdmgpio0", Standard
+ "mdmgpio1", Standard
+ "mdmgpio2", Standard
+ "mdmgpio3", Standard
+ "mdmgpio4", Standard
+ "mdmgpio5", Standard
+ "mdmgpio6", Standard
+ "mdmgpio7", Standard
+ "mdmgpio8", Standard
+ "mphi_data_0", Standard
+ "mphi_data_1", Standard
+ "mphi_data_2", Standard
+ "mphi_data_3", Standard
+ "mphi_data_4", Standard
+ "mphi_data_5", Standard
+ "mphi_data_6", Standard
+ "mphi_data_7", Standard
+ "mphi_data_8", Standard
+ "mphi_data_9", Standard
+ "mphi_data_10", Standard
+ "mphi_data_11", Standard
+ "mphi_data_12", Standard
+ "mphi_data_13", Standard
+ "mphi_data_14", Standard
+ "mphi_data_15", Standard
+ "mphi_ha0", Standard
+ "mphi_hat0", Standard
+ "mphi_hat1", Standard
+ "mphi_hce0_n", Standard
+ "mphi_hce1_n", Standard
+ "mphi_hrd_n", Standard
+ "mphi_hwr_n", Standard
+ "mphi_run0", Standard
+ "mphi_run1", Standard
+ "mtx_scan_clk", Standard
+ "mtx_scan_data", Standard
+ "nand_ad_0", Standard
+ "nand_ad_1", Standard
+ "nand_ad_2", Standard
+ "nand_ad_3", Standard
+ "nand_ad_4", Standard
+ "nand_ad_5", Standard
+ "nand_ad_6", Standard
+ "nand_ad_7", Standard
+ "nand_ale", Standard
+ "nand_cen_0", Standard
+ "nand_cen_1", Standard
+ "nand_cle", Standard
+ "nand_oen", Standard
+ "nand_rdy_0", Standard
+ "nand_rdy_1", Standard
+ "nand_wen", Standard
+ "nand_wp", Standard
+ "pc1", Standard
+ "pc2", Standard
+ "pmu_int", Standard
+ "pmu_scl", I2C
+ "pmu_sda", I2C
+ "rfst2g_mtsloten3g", Standard
+ "rgmii_0_rx_ctl", Standard
+ "rgmii_0_rxc", Standard
+ "rgmii_0_rxd_0", Standard
+ "rgmii_0_rxd_1", Standard
+ "rgmii_0_rxd_2", Standard
+ "rgmii_0_rxd_3", Standard
+ "rgmii_0_tx_ctl", Standard
+ "rgmii_0_txc", Standard
+ "rgmii_0_txd_0", Standard
+ "rgmii_0_txd_1", Standard
+ "rgmii_0_txd_2", Standard
+ "rgmii_0_txd_3", Standard
+ "rgmii_1_rx_ctl", Standard
+ "rgmii_1_rxc", Standard
+ "rgmii_1_rxd_0", Standard
+ "rgmii_1_rxd_1", Standard
+ "rgmii_1_rxd_2", Standard
+ "rgmii_1_rxd_3", Standard
+ "rgmii_1_tx_ctl", Standard
+ "rgmii_1_txc", Standard
+ "rgmii_1_txd_0", Standard
+ "rgmii_1_txd_1", Standard
+ "rgmii_1_txd_2", Standard
+ "rgmii_1_txd_3", Standard
+ "rgmii_gpio_0", Standard
+ "rgmii_gpio_1", Standard
+ "rgmii_gpio_2", Standard
+ "rgmii_gpio_3", Standard
+ "rtxdata2g_txdata3g1", Standard
+ "rtxen2g_txdata3g2", Standard
+ "rxdata3g0", Standard
+ "rxdata3g1", Standard
+ "rxdata3g2", Standard
+ "sdio1_clk", Standard
+ "sdio1_cmd", Standard
+ "sdio1_data_0", Standard
+ "sdio1_data_1", Standard
+ "sdio1_data_2", Standard
+ "sdio1_data_3", Standard
+ "sdio4_clk", Standard
+ "sdio4_cmd", Standard
+ "sdio4_data_0", Standard
+ "sdio4_data_1", Standard
+ "sdio4_data_2", Standard
+ "sdio4_data_3", Standard
+ "sim_clk", Standard
+ "sim_data", Standard
+ "sim_det", Standard
+ "sim_resetn", Standard
+ "sim2_clk", Standard
+ "sim2_data", Standard
+ "sim2_det", Standard
+ "sim2_resetn", Standard
+ "sri_c", Standard
+ "sri_d", Standard
+ "sri_e", Standard
+ "ssp_extclk", Standard
+ "ssp0_clk", Standard
+ "ssp0_fs", Standard
+ "ssp0_rxd", Standard
+ "ssp0_txd", Standard
+ "ssp2_clk", Standard
+ "ssp2_fs_0", Standard
+ "ssp2_fs_1", Standard
+ "ssp2_fs_2", Standard
+ "ssp2_fs_3", Standard
+ "ssp2_rxd_0", Standard
+ "ssp2_rxd_1", Standard
+ "ssp2_txd_0", Standard
+ "ssp2_txd_1", Standard
+ "ssp3_clk", Standard
+ "ssp3_fs", Standard
+ "ssp3_rxd", Standard
+ "ssp3_txd", Standard
+ "ssp4_clk", Standard
+ "ssp4_fs", Standard
+ "ssp4_rxd", Standard
+ "ssp4_txd", Standard
+ "ssp5_clk", Standard
+ "ssp5_fs", Standard
+ "ssp5_rxd", Standard
+ "ssp5_txd", Standard
+ "ssp6_clk", Standard
+ "ssp6_fs", Standard
+ "ssp6_rxd", Standard
+ "ssp6_txd", Standard
+ "stat_1", Standard
+ "stat_2", Standard
+ "sysclken", Standard
+ "traceclk", Standard
+ "tracedt00", Standard
+ "tracedt01", Standard
+ "tracedt02", Standard
+ "tracedt03", Standard
+ "tracedt04", Standard
+ "tracedt05", Standard
+ "tracedt06", Standard
+ "tracedt07", Standard
+ "tracedt08", Standard
+ "tracedt09", Standard
+ "tracedt10", Standard
+ "tracedt11", Standard
+ "tracedt12", Standard
+ "tracedt13", Standard
+ "tracedt14", Standard
+ "tracedt15", Standard
+ "txdata3g0", Standard
+ "txpwrind", Standard
+ "uartb1_ucts", Standard
+ "uartb1_urts", Standard
+ "uartb1_urxd", Standard
+ "uartb1_utxd", Standard
+ "uartb2_urxd", Standard
+ "uartb2_utxd", Standard
+ "uartb3_ucts", Standard
+ "uartb3_urts", Standard
+ "uartb3_urxd", Standard
+ "uartb3_utxd", Standard
+ "uartb4_ucts", Standard
+ "uartb4_urts", Standard
+ "uartb4_urxd", Standard
+ "uartb4_utxd", Standard
+ "vc_cam1_scl", I2C
+ "vc_cam1_sda", I2C
+ "vc_cam2_scl", I2C
+ "vc_cam2_sda", I2C
+ "vc_cam3_scl", I2C
+ "vc_cam3_sda", I2C
diff --git a/Documentation/devicetree/bindings/pinctrl/fsl,imx25-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/fsl,imx25-pinctrl.txt
new file mode 100644
index 00000000000..fd653bde18d
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/fsl,imx25-pinctrl.txt
@@ -0,0 +1,23 @@
+* Freescale IMX25 IOMUX Controller
+
+Please refer to fsl,imx-pinctrl.txt in this directory for common binding part
+and usage.
+
+CONFIG bits definition:
+PAD_CTL_HYS (1 << 8)
+PAD_CTL_PKE (1 << 7)
+PAD_CTL_PUE (1 << 6)
+PAD_CTL_PUS_100K_DOWN (0 << 4)
+PAD_CTL_PUS_47K_UP (1 << 4)
+PAD_CTL_PUS_100K_UP (2 << 4)
+PAD_CTL_PUS_22K_UP (3 << 4)
+PAD_CTL_ODE_CMOS (0 << 3)
+PAD_CTL_ODE_OPENDRAIN (1 << 3)
+PAD_CTL_DSE_NOMINAL (0 << 1)
+PAD_CTL_DSE_HIGH (1 << 1)
+PAD_CTL_DSE_MAX (2 << 1)
+PAD_CTL_SRE_FAST (1 << 0)
+PAD_CTL_SRE_SLOW (0 << 0)
+
+Refer to imx25-pinfunc.h in device tree source folder for all available
+imx25 PIN_FUNC_ID.
diff --git a/Documentation/devicetree/bindings/pinctrl/fsl,imx27-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/fsl,imx27-pinctrl.txt
index 353eca0efbf..d1706ea8257 100644
--- a/Documentation/devicetree/bindings/pinctrl/fsl,imx27-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/fsl,imx27-pinctrl.txt
@@ -52,12 +52,25 @@ Required properties for pin configuration node:
CONFIG can be 0 or 1, meaning Pullup disable/enable.
+The iomux controller has gpio child nodes which are embedded in the iomux
+control registers. They have to be defined as child nodes of the iomux device
+node. If gpio subnodes are defined "#address-cells", "#size-cells" and "ranges"
+properties for the iomux device node are required.
Example:
iomuxc: iomuxc@10015000 {
compatible = "fsl,imx27-iomuxc";
reg = <0x10015000 0x600>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+
+ gpio1: gpio@10015000 {
+ ...
+ };
+
+ ...
uart {
pinctrl_uart1: uart-1 {
@@ -83,6 +96,15 @@ The above example using macros:
iomuxc: iomuxc@10015000 {
compatible = "fsl,imx27-iomuxc";
reg = <0x10015000 0x600>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+
+ gpio1: gpio@10015000 {
+ ...
+ };
+
+ ...
uart {
pinctrl_uart1: uart-1 {
diff --git a/Documentation/devicetree/bindings/pinctrl/nvidia,tegra124-pinmux.txt b/Documentation/devicetree/bindings/pinctrl/nvidia,tegra124-pinmux.txt
new file mode 100644
index 00000000000..6464bf76946
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/nvidia,tegra124-pinmux.txt
@@ -0,0 +1,144 @@
+NVIDIA Tegra124 pinmux controller
+
+The Tegra124 pinctrl binding is very similar to the Tegra20 and Tegra30
+pinctrl binding, as described in nvidia,tegra20-pinmux.txt and
+nvidia,tegra30-pinmux.txt. In fact, this document assumes that binding as
+a baseline, and only documents the differences between the two bindings.
+
+Required properties:
+- compatible: "nvidia,tegra124-pinmux"
+- reg: Should contain a list of base address and size pairs for:
+ -- first entry - the drive strength and pad control registers.
+ -- second entry - the pinmux registers
+
+Tegra124 adds the following optional properties for pin configuration subnodes.
+The macros for options are defined in the
+ include/dt-binding/pinctrl/pinctrl-tegra.h.
+- nvidia,enable-input: Integer. Enable the pin's input path.
+ enable :TEGRA_PIN_ENABLE0 and
+ disable or output only: TEGRA_PIN_DISABLE.
+- nvidia,open-drain: Integer.
+ enable: TEGRA_PIN_ENABLE.
+ disable: TEGRA_PIN_DISABLE.
+- nvidia,lock: Integer. Lock the pin configuration against further changes
+ until reset.
+ enable: TEGRA_PIN_ENABLE.
+ disable: TEGRA_PIN_DISABLE.
+- nvidia,io-reset: Integer. Reset the IO path.
+ enable: TEGRA_PIN_ENABLE.
+ disable: TEGRA_PIN_DISABLE.
+- nvidia,rcv-sel: Integer. Select VIL/VIH receivers.
+ normal: TEGRA_PIN_DISABLE
+ high: TEGRA_PIN_ENABLE
+
+Please refer the Tegra TRM for complete details regarding which groups
+support which functionality.
+
+Valid values for pin and group names are:
+
+ per-pin mux groups:
+
+ These all support nvidia,function, nvidia,tristate, nvidia,pull,
+ nvidia,enable-input. Some support nvidia,lock nvidia,open-drain,
+ nvidia,io-reset and nvidia,rcv-sel.
+
+ ulpi_data0_po1, ulpi_data1_po2, ulpi_data2_po3, ulpi_data3_po4,
+ ulpi_data4_po5, ulpi_data5_po6, ulpi_data6_po7, ulpi_data7_po0,
+ ulpi_clk_py0, ulpi_dir_py1, ulpi_nxt_py2, ulpi_stp_py3, dap3_fs_pp0,
+ dap3_din_pp1, dap3_dout_pp2, dap3_sclk_pp3, pv0, pv1, sdmmc1_clk_pz0,
+ sdmmc1_cmd_pz1, sdmmc1_dat3_py4, sdmmc1_dat2_py5, sdmmc1_dat1_py6,
+ sdmmc1_dat0_py7, clk2_out_pw5, clk2_req_pcc5, hdmi_int_pn7, ddc_scl_pv4,
+ ddc_sda_pv5, uart2_rxd_pc3, uart2_txd_pc2, uart2_rts_n_pj6,
+ uart2_cts_n_pj5, uart3_txd_pw6, uart3_rxd_pw7, uart3_cts_n_pa1,
+ uart3_rts_n_pc0, pu0, pu1, pu2, pu3, pu4, pu5, pu6, gen1_i2c_scl_pc4,
+ gen1_i2c_sda_pc5, dap4_fs_pp4, dap4_din_pp5, dap4_dout_pp6,
+ dap4_sclk_pp7, clk3_out_pee0, clk3_req_pee1, pc7, pi5, pi7, pk0, pk1,
+ pj0, pj2, pk3, pk4, pk2, pi3, pi6, pg0, pg1, pg2, pg3, pg4, pg5, pg6,
+ pg7, ph0, ph1, ph2, ph3, ph4, ph5, ph6, ph7, pj7, pb0, pb1, pk7, pi0,
+ pi1, pi2, pi4, gen2_i2c_scl_pt5, gen2_i2c_sda_pt6, sdmmc4_clk_pcc4,
+ sdmmc4_cmd_pt7, sdmmc4_dat0_paa0, sdmmc4_dat1_paa1, sdmmc4_dat2_paa2,
+ sdmmc4_dat3_paa3, sdmmc4_dat4_paa4, sdmmc4_dat5_paa5, sdmmc4_dat6_paa6,
+ sdmmc4_dat7_paa7, cam_mclk_pcc0, pcc1, pbb0, cam_i2c_scl_pbb1,
+ cam_i2c_sda_pbb2, pbb3, pbb4, pbb5, pbb6, pbb7, pcc2, jtag_rtck,
+ pwr_i2c_scl_pz6, pwr_i2c_sda_pz7, kb_row0_pr0, kb_row1_pr1, kb_row2_pr2,
+ kb_row3_pr3, kb_row4_pr4, kb_row5_pr5, kb_row6_pr6, kb_row7_pr7,
+ kb_row8_ps0, kb_row9_ps1, kb_row10_ps2, kb_row11_ps3, kb_row12_ps4,
+ kb_row13_ps5, kb_row14_ps6, kb_row15_ps7, kb_col0_pq0, kb_col1_pq1,
+ kb_col2_pq2, kb_col3_pq3, kb_col4_pq4, kb_col5_pq5, kb_col6_pq6,
+ kb_col7_pq7, clk_32k_out_pa0, core_pwr_req, cpu_pwr_req, pwr_int_n,
+ clk_32k_in, owr, dap1_fs_pn0, dap1_din_pn1, dap1_dout_pn2,
+ dap1_sclk_pn3, dap_mclk1_req_pee2, dap_mclk1_pw4, spdif_in_pk6,
+ spdif_out_pk5, dap2_fs_pa2, dap2_din_pa4, dap2_dout_pa5, dap2_sclk_pa3,
+ dvfs_pwm_px0, gpio_x1_aud_px1, gpio_x3_aud_px3, dvfs_clk_px2,
+ gpio_x4_aud_px4, gpio_x5_aud_px5, gpio_x6_aud_px6, gpio_x7_aud_px7,
+ sdmmc3_clk_pa6, sdmmc3_cmd_pa7, sdmmc3_dat0_pb7, sdmmc3_dat1_pb6,
+ sdmmc3_dat2_pb5, sdmmc3_dat3_pb4, pex_l0_rst_n_pdd1,
+ pex_l0_clkreq_n_pdd2, pex_wake_n_pdd3, pex_l1_rst_n_pdd5,
+ pex_l1_clkreq_n_pdd6, hdmi_cec_pee3, sdmmc1_wp_n_pv3,
+ sdmmc3_cd_n_pv2, gpio_w2_aud_pw2, gpio_w3_aud_pw3, usb_vbus_en0_pn4,
+ usb_vbus_en1_pn5, sdmmc3_clk_lb_out_pee4, sdmmc3_clk_lb_in_pee5,
+ gmi_clk_lb, reset_out_n, kb_row16_pt0, kb_row17_pt1, usb_vbus_en2_pff1,
+ pff2, dp_hpd_pff0,
+
+ drive groups:
+
+ These all support nvidia,pull-down-strength, nvidia,pull-up-strength,
+ nvidia,slew-rate-rising, nvidia,slew-rate-falling. Most but not all
+ support nvidia,high-speed-mode, nvidia,schmitt, nvidia,low-power-mode
+ and nvidia,drive-type.
+
+ ao1, ao2, at1, at2, at3, at4, at5, cdev1, cdev2, dap1, dap2, dap3, dap4,
+ dbg, sdio3, spi, uaa, uab, uart2, uart3, sdio1, ddc, gma, gme, gmf, gmg,
+ gmh, owr, uda, gpv, dev3, cec, usb_vbus_en, ao3, ao0, hv0, sdio4, ao4.
+
+Valid values for nvidia,functions are:
+
+ blink, cec, cldvfs, clk12, cpu, dap, dap1, dap2, dev3, displaya,
+ displaya_alt, displayb, dtv, extperiph1, extperiph2, extperiph3,
+ gmi, gmi_alt, hda, hsi, i2c1, i2c2, i2c3, i2c4, i2cpwr, i2s0,
+ i2s1, i2s2, i2s3, i2s4, irda, kbc, owr, pmi, pwm0, pwm1, pwm2, pwm3,
+ pwron, reset_out_n, rsvd1, rsvd2, rsvd3, rsvd4, sdmmc1, sdmmc2, sdmmc3,
+ sdmmc4, soc, spdif, spi1, spi2, spi3, spi4, spi5, spi6, trace, uarta,
+ uartb, uartc, uartd, ulpi, usb, vgp1, vgp2, vgp3, vgp4, vgp5, vgp6,
+ vi, vi_alt1, vi_alt3, vimclk2, vimclk2_alt, sata, ccla, pe0, pe, pe1,
+ dp, rtck, sys, clk tmds.
+
+Example:
+
+ pinmux: pinmux {
+ compatible = "nvidia,tegra124-pinmux";
+ reg = <0x70000868 0x164 /* Pad control registers */
+ 0x70003000 0x434>; /* PinMux registers */
+ };
+
+Example pinmux entries:
+
+ pinctrl {
+ sdmmc4_default: pinmux {
+ sdmmc4_clk_pcc4 {
+ nvidia,pins = "sdmmc4_clk_pcc4",
+ nvidia,function = "sdmmc4";
+ nvidia,pull = <TEGRA_PIN_PULL_NONE>;
+ nvidia,tristate = <TEGRA_PIN_DISABLE>;
+ };
+
+ sdmmc4_dat0_paa0 {
+ nvidia,pins = "sdmmc4_dat0_paa0",
+ "sdmmc4_dat1_paa1",
+ "sdmmc4_dat2_paa2",
+ "sdmmc4_dat3_paa3",
+ "sdmmc4_dat4_paa4",
+ "sdmmc4_dat5_paa5",
+ "sdmmc4_dat6_paa6",
+ "sdmmc4_dat7_paa7";
+ nvidia,function = "sdmmc4";
+ nvidia,pull = <TEGRA_PIN_PULL_UP>;
+ nvidia,tristate = <TEGRA_PIN_DISABLE>;
+ };
+ };
+ };
+
+ sdhci@78000400 {
+ pinctrl-names = "default";
+ pinctrl-0 = <&sdmmc4_default>;
+ };
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
index 1958ca9f9e5..4414163e76d 100644
--- a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
@@ -151,6 +151,8 @@ 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-enable - enable input on pin (no effect on output)
+input-disable - disable input on pin (no effect on output)
input-schmitt-enable - enable schmitt-trigger mode
input-schmitt-disable - disable schmitt-trigger mode
input-debounce - debounce mode with debound time X
@@ -158,6 +160,7 @@ low-power-enable - enable low power mode
low-power-disable - disable 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
+slew-rate - set the slew rate
Some of the generic properties take arguments. For those that do, the
arguments are described below.
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-single.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-single.txt
index 7069a0b84e3..bc0dfdfdb14 100644
--- a/Documentation/devicetree/bindings/pinctrl/pinctrl-single.txt
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-single.txt
@@ -98,7 +98,7 @@ below for more information.
In case when one register changes more than one pin's mux the
pinctrl-single,bits need to be used which takes three parameters:
- pinctrl-single,bits = <0xdc 0x18, 0xff>;
+ pinctrl-single,bits = <0xdc 0x18 0xff>;
Where 0xdc is the offset from the pinctrl register base address for the
device pinctrl register, 0x18 is the desired value, and 0xff is the sub mask to
diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,msm8974-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/qcom,msm8974-pinctrl.txt
new file mode 100644
index 00000000000..4c352be5dd6
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/qcom,msm8974-pinctrl.txt
@@ -0,0 +1,92 @@
+Qualcomm MSM8974 TLMM block
+
+Required properties:
+- compatible: "qcom,msm8x74-pinctrl"
+- reg: Should be the base address and length of the TLMM block.
+- interrupts: Should be the parent IRQ of the TLMM block.
+- interrupt-controller: Marks the device node as an interrupt controller.
+- #interrupt-cells: Should be two.
+- gpio-controller: Marks the device node as a GPIO controller.
+- #gpio-cells : Should be two.
+ The first cell is the gpio pin number and the
+ second cell is used for optional parameters.
+
+Please refer to ../gpio/gpio.txt and ../interrupt-controller/interrupts.txt for
+a general description of GPIO and interrupt bindings.
+
+Please refer to pinctrl-bindings.txt in this directory for details of the
+common pinctrl bindings used by client devices, including the meaning of the
+phrase "pin configuration node".
+
+Qualcomm's pin configuration nodes act as a container for an abitrary number of
+subnodes. Each of these subnodes represents some desired configuration for a
+pin, a group, or a list of pins or groups. This configuration can include the
+mux function to select on those pin(s)/group(s), and various pin configuration
+parameters, such as pull-up, drive strength, etc.
+
+The name of each subnode is not important; all subnodes should be enumerated
+and processed purely based on their content.
+
+Each subnode only affects those parameters that are explicitly listed. In
+other words, a subnode that lists a mux function but no pin configuration
+parameters implies no information about any pin configuration parameters.
+Similarly, a pin subnode that describes a pullup parameter implies no
+information about e.g. the mux function.
+
+
+The following generic properties as defined in pinctrl-bindings.txt are valid
+to specify in a pin configuration subnode:
+ pins, function, bias-disable, bias-pull-down, bias-pull,up, drive-strength.
+
+Non-empty subnodes must specify the 'pins' property.
+Note that not all properties are valid for all pins.
+
+
+Valid values for qcom,pins are:
+ gpio0-gpio145
+ Supports mux, bias and drive-strength
+
+ sdc1_clk, sdc1_cmd, sdc1_data, sdc2_clk, sdc2_cmd, sdc2_data
+ Supports bias and drive-strength
+
+Valid values for qcom,function are:
+ blsp_i2c2, blsp_i2c6, blsp_i2c11, blsp_spi1, blsp_uart2, blsp_uart8, slimbus
+
+ (Note that this is not yet the complete list of functions)
+
+
+
+Example:
+
+ msmgpio: pinctrl@fd510000 {
+ compatible = "qcom,msm8974-pinctrl";
+ reg = <0xfd510000 0x4000>;
+
+ gpio-controller;
+ #gpio-cells = <2>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ interrupts = <0 208 0>;
+
+ pinctrl-names = "default";
+ pinctrl-0 = <&uart2_default>;
+
+ uart2_default: uart2_default {
+ mux {
+ qcom,pins = "gpio4", "gpio5";
+ qcom,function = "blsp_uart2";
+ };
+
+ tx {
+ qcom,pins = "gpio4";
+ drive-strength = <4>;
+ bias-disable;
+ };
+
+ rx {
+ qcom,pins = "gpio5";
+ drive-strength = <2>;
+ bias-pull-up;
+ };
+ };
+ };
diff --git a/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt
index d5dac7b843a..35d2e1f186f 100644
--- a/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt
@@ -26,6 +26,11 @@ Optional properties:
- #gpio-range-cells: Mandatory when the PFC doesn't handle GPIO, forbidden
otherwise. Should be 3.
+ - interrupts-extended: Specify the interrupts associated with external
+ IRQ pins. This property is mandatory when the PFC handles GPIOs and
+ forbidden otherwise. When specified, it must contain one interrupt per
+ external IRQ, sorted by external IRQ number.
+
The PFC node also acts as a container for pin configuration nodes. Please refer
to pinctrl-bindings.txt in this directory for the definition of the term "pin
configuration node" and for the common pinctrl bindings used by client devices.
@@ -103,6 +108,15 @@ Example 1: SH73A0 (SH-Mobile AG5) pin controller node
<0xe605801c 0x1c>;
gpio-controller;
#gpio-cells = <2>;
+ interrupts-extended =
+ <&irqpin0 0 0>, <&irqpin0 1 0>, <&irqpin0 2 0>, <&irqpin0 3 0>,
+ <&irqpin0 4 0>, <&irqpin0 5 0>, <&irqpin0 6 0>, <&irqpin0 7 0>,
+ <&irqpin1 0 0>, <&irqpin1 1 0>, <&irqpin1 2 0>, <&irqpin1 3 0>,
+ <&irqpin1 4 0>, <&irqpin1 5 0>, <&irqpin1 6 0>, <&irqpin1 7 0>,
+ <&irqpin2 0 0>, <&irqpin2 1 0>, <&irqpin2 2 0>, <&irqpin2 3 0>,
+ <&irqpin2 4 0>, <&irqpin2 5 0>, <&irqpin2 6 0>, <&irqpin2 7 0>,
+ <&irqpin3 0 0>, <&irqpin3 1 0>, <&irqpin3 2 0>, <&irqpin3 3 0>,
+ <&irqpin3 4 0>, <&irqpin3 5 0>, <&irqpin3 6 0>, <&irqpin3 7 0>;
};
Example 2: A GPIO LED node that references a GPIO
diff --git a/Documentation/pinctrl.txt b/Documentation/pinctrl.txt
index a7929cb47e7..23f1590f49f 100644
--- a/Documentation/pinctrl.txt
+++ b/Documentation/pinctrl.txt
@@ -18,7 +18,7 @@ Definition of PIN CONTROLLER:
- A pin controller is a piece of hardware, usually a set of registers, that
can control PINs. It may be able to multiplex, bias, set load capacitance,
- set drive strength etc for individual pins or groups of pins.
+ set drive strength, etc. for individual pins or groups of pins.
Definition of PIN:
@@ -90,7 +90,7 @@ selected drivers, you need to select them from your machine's Kconfig entry,
since these are so tightly integrated with the machines they are used on.
See for example arch/arm/mach-u300/Kconfig for an example.
-Pins usually have fancier names than this. You can find these in the dataheet
+Pins usually have fancier names than this. You can find these in the datasheet
for your chip. Notice that the core pinctrl.h file provides a fancy macro
called PINCTRL_PIN() to create the struct entries. As you can see I enumerated
the pins from 0 in the upper left corner to 63 in the lower right corner.
@@ -185,7 +185,7 @@ static struct pinctrl_desc foo_desc = {
};
The pin control subsystem will call the .get_groups_count() function to
-determine total number of legal selectors, then it will call the other functions
+determine the total number of legal selectors, then it will call the other functions
to retrieve the name and pins of the group. Maintaining the data structure of
the groups is up to the driver, this is just a simple example - in practice you
may need more entries in your group structure, for example specific register
@@ -195,7 +195,7 @@ ranges associated with each group and so on.
Pin configuration
=================
-Pins can sometimes be software-configured in an various ways, mostly related
+Pins can sometimes be software-configured in various ways, mostly related
to their electronic properties when used as inputs or outputs. For example you
may be able to make an output pin high impedance, or "tristate" meaning it is
effectively disconnected. You may be able to connect an input pin to VDD or GND
@@ -291,7 +291,7 @@ Since the pin controller subsystem have its pinspace local to the pin
controller we need a mapping so that the pin control subsystem can figure out
which pin controller handles control of a certain GPIO pin. Since a single
pin controller may be muxing several GPIO ranges (typically SoCs that have
-one set of pins but internally several GPIO silicon blocks, each modelled as
+one set of pins, but internally several GPIO silicon blocks, each modelled as
a struct gpio_chip) any number of GPIO ranges can be added to a pin controller
instance like this:
@@ -373,9 +373,9 @@ will be called on that specific pin controller.
For all functionalities dealing with pin biasing, pin muxing etc, the pin
controller subsystem will look up the corresponding pin number from the passed
-in gpio number, and use the range's internals to retrive a pin number. After
+in gpio number, and use the range's internals to retrieve a pin number. After
that, the subsystem passes it on to the pin control driver, so the driver
-will get an pin number into its handled number range. Further it is also passed
+will get a pin number into its handled number range. Further it is also passed
the range ID value, so that the pin controller knows which range it should
deal with.
@@ -430,8 +430,8 @@ pins you see some will be taken by things like a few VCC and GND to feed power
to the chip, and quite a few will be taken by large ports like an external
memory interface. The remaining pins will often be subject to pin multiplexing.
-The example 8x8 PGA package above will have pin numbers 0 thru 63 assigned to
-its physical pins. It will name the pins { A1, A2, A3 ... H6, H7, H8 } using
+The example 8x8 PGA package above will have pin numbers 0 through 63 assigned
+to its physical pins. It will name the pins { A1, A2, A3 ... H6, H7, H8 } using
pinctrl_register_pins() and a suitable data set as shown earlier.
In this 8x8 BGA package the pins { A8, A7, A6, A5 } can be used as an SPI port
@@ -442,7 +442,7 @@ we cannot use the SPI port and I2C port at the same time. However in the inside
of the package the silicon performing the SPI logic can alternatively be routed
out on pins { G4, G3, G2, G1 }.
-On the botton row at { A1, B1, C1, D1, E1, F1, G1, H1 } we have something
+On the bottom row at { A1, B1, C1, D1, E1, F1, G1, H1 } we have something
special - it's an external MMC bus that can be 2, 4 or 8 bits wide, and it will
consume 2, 4 or 8 pins respectively, so either { A1, B1 } are taken or
{ A1, B1, C1, D1 } or all of them. If we use all 8 bits, we cannot use the SPI
@@ -549,7 +549,7 @@ Assumptions:
We assume that the number of possible function maps to pin groups is limited by
the hardware. I.e. we assume that there is no system where any function can be
-mapped to any pin, like in a phone exchange. So the available pins groups for
+mapped to any pin, like in a phone exchange. So the available pin groups for
a certain function will be limited to a few choices (say up to eight or so),
not hundreds or any amount of choices. This is the characteristic we have found
by inspecting available pinmux hardware, and a necessary assumption since we
@@ -564,7 +564,7 @@ The pinmux core takes care of preventing conflicts on pins and calling
the pin controller driver to execute different settings.
It is the responsibility of the pinmux driver to impose further restrictions
-(say for example infer electronic limitations due to load etc) to determine
+(say for example infer electronic limitations due to load, etc.) to determine
whether or not the requested function can actually be allowed, and in case it
is possible to perform the requested mux setting, poke the hardware so that
this happens.
@@ -755,7 +755,7 @@ Pin control interaction with the GPIO subsystem
Note that the following implies that the use case is to use a certain pin
from the Linux kernel using the API in <linux/gpio.h> with gpio_request()
and similar functions. There are cases where you may be using something
-that your datasheet calls "GPIO mode" but actually is just an electrical
+that your datasheet calls "GPIO mode", but actually is just an electrical
configuration for a certain device. See the section below named
"GPIO mode pitfalls" for more details on this scenario.
@@ -871,7 +871,7 @@ hardware and shall be put into different subsystems:
- Registers (or fields within registers) that control muxing of signals
from various other HW blocks (e.g. I2C, MMC, or GPIO) onto pins should
- be exposed through the pinctrl subssytem, as mux functions.
+ be exposed through the pinctrl subsystem, as mux functions.
- Registers (or fields within registers) that control GPIO functionality
such as setting a GPIO's output value, reading a GPIO's input value, or
@@ -895,7 +895,7 @@ Example: a pin is usually muxed in to be used as a UART TX line. But during
system sleep, we need to put this pin into "GPIO mode" and ground it.
If you make a 1-to-1 map to the GPIO subsystem for this pin, you may start
-to think that you need to come up with something real complex, that the
+to think that you need to come up with something really complex, that the
pin shall be used for UART TX and GPIO at the same time, that you will grab
a pin control handle and set it to a certain state to enable UART TX to be
muxed in, then twist it over to GPIO mode and use gpio_direction_output()
@@ -964,12 +964,12 @@ GPIO mode.
This will give the desired effect without any bogus interaction with the
GPIO subsystem. It is just an electrical configuration used by that device
when going to sleep, it might imply that the pin is set into something the
-datasheet calls "GPIO mode" but that is not the point: it is still used
+datasheet calls "GPIO mode", but that is not the point: it is still used
by that UART device to control the pins that pertain to that very UART
driver, putting them into modes needed by the UART. GPIO in the Linux
kernel sense are just some 1-bit line, and is a different use case.
-How the registers are poked to attain the push/pull and output low
+How the registers are poked to attain the push or pull, and output low
configuration and the muxing of the "u0" or "gpio-mode" group onto these
pins is a question for the driver.
@@ -977,7 +977,7 @@ Some datasheets will be more helpful and refer to the "GPIO mode" as
"low power mode" rather than anything to do with GPIO. This often means
the same thing electrically speaking, but in this latter case the
software engineers will usually quickly identify that this is some
-specific muxing/configuration rather than anything related to the GPIO
+specific muxing or configuration rather than anything related to the GPIO
API.
@@ -1024,8 +1024,7 @@ up the device struct (just like with clockdev or regulators). The function name
must match a function provided by the pinmux driver handling this pin range.
As you can see we may have several pin controllers on the system and thus
-we need to specify which one of them that contain the functions we wish
-to map.
+we need to specify which one of them contains the functions we wish to map.
You register this pinmux mapping to the pinmux subsystem by simply:
@@ -1254,10 +1253,10 @@ The semantics of the pinctrl APIs are:
pinctrl_get().
- pinctrl_lookup_state() is called in process context to obtain a handle to a
- specific state for a the client device. This operation may be slow too.
+ specific state for a client device. This operation may be slow, too.
- pinctrl_select_state() programs pin controller hardware according to the
- definition of the state as given by the mapping table. In theory this is a
+ definition of the state as given by the mapping table. In theory, this is a
fast-path operation, since it only involved blasting some register settings
into hardware. However, note that some pin controllers may have their
registers on a slow/IRQ-based bus, so client devices should not assume they