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authorGrygorii Strashko <grygorii.strashko@ti.com>2014-09-03 20:05:34 +0300
committerLinus Walleij <linus.walleij@linaro.org>2014-09-16 14:42:16 -0700
commit2134cb997f2f1b2d960ad8705d67dc8d690ba59c (patch)
tree097a63db8464dc86af25ba9480a21ed21105cd34
parent5a3e3f88b0a10f8b5baf224ebda5916195fb8745 (diff)
gpio: syscon: reuse for keystone 2 socs
On Keystone SOCs, ARM host can send interrupts to DSP cores using the DSP GPIO controller IP. Each DSP GPIO controller provides 28 IRQ signals for each DSP core. This is one of the component used by the IPC mechanism used on Keystone SOCs. Keystone 2 DSP GPIO controller has specific features: - each GPIO can be configured only as output pin; - setting GPIO value to 1 causes IRQ generation on target DSP core; - reading pin value returns 0 - if IRQ was handled or 1 - IRQ is still pending. This patch updates gpio-syscon driver to be reused by Keystone 2 SoCs, because the Keystone 2 DSP GPIO controller is controlled through Syscon devices and, as requested by Linus Walleij, such kind of GPIO controllers should be integrated with drivers/gpio/gpio-syscon.c driver. Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-dsp-keystone.txt39
-rw-r--r--drivers/gpio/gpio-syscon.c35
2 files changed, 74 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-dsp-keystone.txt b/Documentation/devicetree/bindings/gpio/gpio-dsp-keystone.txt
new file mode 100644
index 000000000000..6c7e6c7302f5
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-dsp-keystone.txt
@@ -0,0 +1,39 @@
+Keystone 2 DSP GPIO controller bindings
+
+HOST OS userland running on ARM can send interrupts to DSP cores using
+the DSP GPIO controller IP. It provides 28 IRQ signals per each DSP core.
+This is one of the component used by the IPC mechanism used on Keystone SOCs.
+
+For example TCI6638K2K SoC has 8 DSP GPIO controllers:
+ - 8 for C66x CorePacx CPUs 0-7
+
+Keystone 2 DSP GPIO controller has specific features:
+- each GPIO can be configured only as output pin;
+- setting GPIO value to 1 causes IRQ generation on target DSP core;
+- reading pin value returns 0 - if IRQ was handled or 1 - IRQ is still
+ pending.
+
+Required Properties:
+- compatible: should be "ti,keystone-dsp-gpio"
+- ti,syscon-dev: phandle/offset pair. The phandle to syscon used to
+ access device state control registers and the offset of device's specific
+ registers within device state control registers range.
+- gpio-controller: Marks the device node as a gpio controller.
+- #gpio-cells: Should be 2.
+
+Please refer to gpio.txt in this directory for details of the common GPIO
+bindings used by client devices.
+
+Example:
+ dspgpio0: keystone_dsp_gpio@02620240 {
+ compatible = "ti,keystone-dsp-gpio";
+ ti,syscon-dev = <&devctrl 0x240>;
+ gpio-controller;
+ #gpio-cells = <2>;
+ };
+
+ dsp0: dsp0 {
+ compatible = "linux,rproc-user";
+ ...
+ kick-gpio = <&dspgpio0 27>;
+ };
diff --git a/drivers/gpio/gpio-syscon.c b/drivers/gpio/gpio-syscon.c
index 049391bf80ee..e82fde4b6898 100644
--- a/drivers/gpio/gpio-syscon.c
+++ b/drivers/gpio/gpio-syscon.c
@@ -140,11 +140,46 @@ static const struct syscon_gpio_data clps711x_mctrl_gpio = {
.dat_bit_offset = 0x40 * 8 + 8,
};
+#define KEYSTONE_LOCK_BIT BIT(0)
+
+static void keystone_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
+{
+ struct syscon_gpio_priv *priv = to_syscon_gpio(chip);
+ unsigned int offs;
+ int ret;
+
+ offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;
+
+ if (!val)
+ return;
+
+ ret = regmap_update_bits(
+ priv->syscon,
+ (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
+ BIT(offs % SYSCON_REG_BITS) | KEYSTONE_LOCK_BIT,
+ BIT(offs % SYSCON_REG_BITS) | KEYSTONE_LOCK_BIT);
+ if (ret < 0)
+ dev_err(chip->dev, "gpio write failed ret(%d)\n", ret);
+}
+
+static const struct syscon_gpio_data keystone_dsp_gpio = {
+ /* ARM Keystone 2 */
+ .compatible = NULL,
+ .flags = GPIO_SYSCON_FEAT_OUT,
+ .bit_count = 28,
+ .dat_bit_offset = 4,
+ .set = keystone_gpio_set,
+};
+
static const struct of_device_id syscon_gpio_ids[] = {
{
.compatible = "cirrus,clps711x-mctrl-gpio",
.data = &clps711x_mctrl_gpio,
},
+ {
+ .compatible = "ti,keystone-dsp-gpio",
+ .data = &keystone_dsp_gpio,
+ },
{ }
};
MODULE_DEVICE_TABLE(of, syscon_gpio_ids);