From: Josef Friedl <josef.fri...@speed.at>

add poweroff driver for mt6323 and make Makefile and Kconfig-Entries

Suggested-by: Frank Wunderlich <fran...@public-files.de>
Signed-off-by: Josef Friedl <josef.fri...@speed.at>
Signed-off-by: Frank Wunderlich <fran...@public-files.de>
Acked-by: Sebastian Reichel <sebastian.reic...@collabora.com>
---
changes since v6: none
changes since v5: split out mfd/mt6397/core.h
changes since v4: none
changes since v3: none
changes since v2: none (=v2 part 5)
---
 drivers/power/reset/Kconfig           | 10 +++
 drivers/power/reset/Makefile          |  1 +
 drivers/power/reset/mt6323-poweroff.c | 97 +++++++++++++++++++++++++++
 3 files changed, 108 insertions(+)
 create mode 100644 drivers/power/reset/mt6323-poweroff.c

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index a564237278ff..c721939767eb 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -140,6 +140,16 @@ config POWER_RESET_LTC2952
          This driver supports an external powerdown trigger and board power
          down via the LTC2952. Bindings are made in the device tree.
 
+config POWER_RESET_MT6323
+       bool "MediaTek MT6323 power-off driver"
+       depends on MFD_MT6397
+       help
+         The power-off driver is responsible for externally shutdown down
+         the power of a remote MediaTek SoC MT6323 is connected to through
+         controlling a tiny circuit BBPU inside MT6323 RTC.
+
+         Say Y if you have a board where MT6323 could be found.
+
 config POWER_RESET_QNAP
        bool "QNAP power-off driver"
        depends on OF_GPIO && PLAT_ORION
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 85da3198e4e0..da37f8b851dc 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
 obj-$(CONFIG_POWER_RESET_GPIO_RESTART) += gpio-restart.o
 obj-$(CONFIG_POWER_RESET_HISI) += hisi-reboot.o
 obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o
+obj-$(CONFIG_POWER_RESET_MT6323) += mt6323-poweroff.o
 obj-$(CONFIG_POWER_RESET_QCOM_PON) += qcom-pon.o
 obj-$(CONFIG_POWER_RESET_OCELOT_RESET) += ocelot-reset.o
 obj-$(CONFIG_POWER_RESET_PIIX4_POWEROFF) += piix4-poweroff.o
diff --git a/drivers/power/reset/mt6323-poweroff.c 
b/drivers/power/reset/mt6323-poweroff.c
new file mode 100644
index 000000000000..1caf43d9e46d
--- /dev/null
+++ b/drivers/power/reset/mt6323-poweroff.c
@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Power off through MediaTek PMIC
+ *
+ * Copyright (C) 2018 MediaTek Inc.
+ *
+ * Author: Sean Wang <sean.w...@mediatek.com>
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/mt6397/core.h>
+#include <linux/mfd/mt6397/rtc.h>
+
+struct mt6323_pwrc {
+       struct device *dev;
+       struct regmap *regmap;
+       u32 base;
+};
+
+static struct mt6323_pwrc *mt_pwrc;
+
+static void mt6323_do_pwroff(void)
+{
+       struct mt6323_pwrc *pwrc = mt_pwrc;
+       unsigned int val;
+       int ret;
+
+       regmap_write(pwrc->regmap, pwrc->base + RTC_BBPU, RTC_BBPU_KEY);
+       regmap_write(pwrc->regmap, pwrc->base + RTC_WRTGR, 1);
+
+       ret = regmap_read_poll_timeout(pwrc->regmap,
+                                       pwrc->base + RTC_BBPU, val,
+                                       !(val & RTC_BBPU_CBUSY),
+                                       MTK_RTC_POLL_DELAY_US,
+                                       MTK_RTC_POLL_TIMEOUT);
+       if (ret)
+               dev_err(pwrc->dev, "failed to write BBPU: %d\n", ret);
+
+       /* Wait some time until system down, otherwise, notice with a warn */
+       mdelay(1000);
+
+       WARN_ONCE(1, "Unable to power off system\n");
+}
+
+static int mt6323_pwrc_probe(struct platform_device *pdev)
+{
+       struct mt6397_chip *mt6397_chip = dev_get_drvdata(pdev->dev.parent);
+       struct mt6323_pwrc *pwrc;
+       struct resource *res;
+
+       pwrc = devm_kzalloc(&pdev->dev, sizeof(*pwrc), GFP_KERNEL);
+       if (!pwrc)
+               return -ENOMEM;
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       pwrc->base = res->start;
+       pwrc->regmap = mt6397_chip->regmap;
+       pwrc->dev = &pdev->dev;
+       mt_pwrc = pwrc;
+
+       pm_power_off = &mt6323_do_pwroff;
+
+       return 0;
+}
+
+static int mt6323_pwrc_remove(struct platform_device *pdev)
+{
+       if (pm_power_off == &mt6323_do_pwroff)
+               pm_power_off = NULL;
+
+       return 0;
+}
+
+static const struct of_device_id mt6323_pwrc_dt_match[] = {
+       { .compatible = "mediatek,mt6323-pwrc" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, mt6323_pwrc_dt_match);
+
+static struct platform_driver mt6323_pwrc_driver = {
+       .probe          = mt6323_pwrc_probe,
+       .remove         = mt6323_pwrc_remove,
+       .driver         = {
+               .name   = "mt6323-pwrc",
+               .of_match_table = mt6323_pwrc_dt_match,
+       },
+};
+
+module_platform_driver(mt6323_pwrc_driver);
+
+MODULE_DESCRIPTION("Poweroff driver for MT6323 PMIC");
+MODULE_AUTHOR("Sean Wang <sean.w...@mediatek.com>");
+MODULE_LICENSE("GPL v2");
-- 
2.17.1

Reply via email to