button: qcom-pmic: introduce Qualcomm PMIC button driver

Qualcomm PMICs include a "pon" function which handles two buttons, the
power button and "resin" button (usually volume down). Introduce a new
driver following upstream Linux DT to enable these and map them to Enter
and Down respectively to enable use in boot menus.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>

diff --git a/MAINTAINERS b/MAINTAINERS
index b5ff934929490438327563b3679dfe1b65063ea7..da477a4e6add646695d7dd8804fe8bdca74fea31 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -575,6 +575,7 @@ M:  Neil Armstrong <neil.armstrong@linaro.org>
 R:     Sumit Garg <sumit.garg@linaro.org>
 S:     Maintained
 F:     arch/arm/mach-snapdragon/
+F:     drivers/button/button-qcom-pmic.c
 F:     drivers/clk/qcom/
 F:     drivers/gpio/msm_gpio.c
 F:     drivers/mmc/msm_sdhci.c

diff --git a/drivers/button/Kconfig b/drivers/button/Kconfig
index 8ce2de37d62a2791c10ccb508936574e162ea7b1..097b05f822e74de2c1b84e7c8d07344418bf8905 100644 (file)
--- a/drivers/button/Kconfig
+++ b/drivers/button/Kconfig
@@ -27,4 +27,13 @@ config BUTTON_GPIO
          The GPIO driver must used driver model. Buttons are configured using
          the device tree.
 
+config BUTTON_QCOM_PMIC
+       bool "Qualcomm power button"
+       depends on BUTTON
+       depends on PMIC_QCOM
+       help
+         Enable support for the power and "resin" (usually volume down) buttons
+         on Qualcomm SoCs. These will be configured as the Enter and Down keys
+         respectively, allowing navigation of bootmenu with buttons on device.
+
 endmenu

diff --git a/drivers/button/Makefile b/drivers/button/Makefile
index bbd18af14940ed469309d2cb73727639df188a80..68555081a47a2eb92e7445f78b0f77568284f1a5 100644 (file)
--- a/drivers/button/Makefile
+++ b/drivers/button/Makefile
@@ -5,3 +5,4 @@
 obj-$(CONFIG_BUTTON) += button-uclass.o
 obj-$(CONFIG_BUTTON_ADC) += button-adc.o
 obj-$(CONFIG_BUTTON_GPIO) += button-gpio.o
+obj-$(CONFIG_BUTTON_QCOM_PMIC) += button-qcom-pmic.o
\ No newline at end of file

diff --git a/drivers/button/button-qcom-pmic.c b/drivers/button/button-qcom-pmic.c
new file mode 100644 (file)
index 0000000..34a976d
--- /dev/null
+++ b/drivers/button/button-qcom-pmic.c
@@ -0,0 +1,165 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Qualcomm generic pmic gpio driver
+ *
+ * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+ * (C) Copyright 2023 Linaro Ltd.
+ */
+
+#include <button.h>
+#include <dt-bindings/input/linux-event-codes.h>
+#include <dm.h>
+#include <dm/device-internal.h>
+#include <dm/lists.h>
+#include <log.h>
+#include <power/pmic.h>
+#include <spmi/spmi.h>
+#include <linux/bitops.h>
+
+#define REG_TYPE               0x4
+#define REG_SUBTYPE            0x5
+
+struct qcom_pmic_btn_priv {
+       u32 base;
+       u32 status_bit;
+       int code;
+       struct udevice *pmic;
+};
+
+#define PON_INT_RT_STS                        0x10
+#define KPDPWR_ON_INT_BIT                     0
+#define RESIN_ON_INT_BIT                      1
+
+#define NODE_IS_PWRKEY(node) (!strncmp(ofnode_get_name(node), "pwrkey", strlen("pwrkey")))
+#define NODE_IS_RESIN(node) (!strncmp(ofnode_get_name(node), "resin", strlen("resin")))
+
+static enum button_state_t qcom_pwrkey_get_state(struct udevice *dev)
+{
+       struct qcom_pmic_btn_priv *priv = dev_get_priv(dev);
+
+       int reg = pmic_reg_read(priv->pmic, priv->base + PON_INT_RT_STS);
+
+       if (reg < 0)
+               return 0;
+
+       return (reg & BIT(priv->status_bit)) != 0;
+}
+
+static int qcom_pwrkey_get_code(struct udevice *dev)
+{
+       struct qcom_pmic_btn_priv *priv = dev_get_priv(dev);
+
+       return priv->code;
+}
+
+static int qcom_pwrkey_probe(struct udevice *dev)
+{
+       struct button_uc_plat *uc_plat = dev_get_uclass_plat(dev);
+       struct qcom_pmic_btn_priv *priv = dev_get_priv(dev);
+       ofnode node = dev_ofnode(dev);
+       int ret;
+       u64 base;
+
+       /* Ignore the top-level pon node */
+       if (!uc_plat->label)
+               return 0;
+
+       /* the pwrkey and resin nodes are children of the "pon" node, get the
+        * PMIC device to use in pmic_reg_* calls.
+        */
+       priv->pmic = dev->parent->parent;
+
+       /* Get the address of the parent pon node */
+       base = dev_read_addr(dev->parent);
+       if (base == FDT_ADDR_T_NONE) {
+               printf("%s: Can't find address\n", dev->name);
+               return -EINVAL;
+       }
+
+       priv->base = base;
+
+       /* Do a sanity check */
+       ret = pmic_reg_read(priv->pmic, priv->base + REG_TYPE);
+       if (ret != 0x1 && ret != 0xb) {
+               printf("%s: unexpected PMIC function type %d\n", dev->name, ret);
+               return -ENXIO;
+       }
+
+       ret = pmic_reg_read(priv->pmic, priv->base + REG_SUBTYPE);
+       if ((ret & 0x7) == 0) {
+               printf("%s: unexpected PMCI function subtype %d\n", dev->name, ret);
+               return -ENXIO;
+       }
+
+       if (NODE_IS_PWRKEY(node)) {
+               priv->status_bit = 0;
+               priv->code = KEY_ENTER;
+       } else if (NODE_IS_RESIN(node)) {
+               priv->status_bit = 1;
+               priv->code = KEY_DOWN;
+       } else {
+               /* Should not get here! */
+               printf("Invalid pon node '%s' should be 'pwrkey' or 'resin'\n",
+                      ofnode_get_name(node));
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static int button_qcom_pmic_bind(struct udevice *parent)
+{
+       struct udevice *dev;
+       ofnode node;
+       int ret;
+
+       dev_for_each_subnode(node, parent) {
+               struct button_uc_plat *uc_plat;
+               const char *label;
+
+               if (!ofnode_is_enabled(node))
+                       continue;
+
+               ret = device_bind_driver_to_node(parent, "qcom_pwrkey",
+                                                ofnode_get_name(node),
+                                                node, &dev);
+               if (ret) {
+                       printf("Failed to bind %s! %d\n", label, ret);
+                       return ret;
+               }
+               uc_plat = dev_get_uclass_plat(dev);
+               if (NODE_IS_PWRKEY(node)) {
+                       uc_plat->label = "pwrkey";
+               } else if (NODE_IS_RESIN(node)) {
+                       uc_plat->label = "vol_down";
+               } else {
+                       printf("Unknown button node '%s' should be 'pwrkey' or 'resin'\n",
+                              ofnode_get_name(node));
+                       device_unbind(dev);
+               }
+       }
+
+       return 0;
+}
+
+static const struct button_ops button_qcom_pmic_ops = {
+       .get_state      = qcom_pwrkey_get_state,
+       .get_code       = qcom_pwrkey_get_code,
+};
+
+static const struct udevice_id qcom_pwrkey_ids[] = {
+       { .compatible = "qcom,pm8916-pon" },
+       { .compatible = "qcom,pm8941-pon" },
+       { .compatible = "qcom,pm8998-pon" },
+       { }
+};
+
+U_BOOT_DRIVER(qcom_pwrkey) = {
+       .name = "qcom_pwrkey",
+       .id = UCLASS_BUTTON,
+       .of_match = qcom_pwrkey_ids,
+       .bind = button_qcom_pmic_bind,
+       .probe = qcom_pwrkey_probe,
+       .ops = &button_qcom_pmic_ops,
+       .priv_auto = sizeof(struct qcom_pmic_btn_priv),
+};