Hi,
On 3/3/23 23:19, Hans de Goede wrote:
> Add a new driver for the power-, wake- and reset-source functionality
> of the Bay Trail (BYT) version of the Crystal Cove PMIC.
>
> The main functionality here is detecting which power-sources (USB /
> DC in / battery) are active. This is normally exposed to userspace as
> a power_supply class charger device with an online sysfs attribute.
>
> But if a charger is online or not is already exposed on BYT-CRC devices
> through either an ACPI AC power_supply device, or through a native driver
> for the battery charger chip (e.g. a BQ24292i).
>
> So instead of adding duplicate info under the power_supply class this
> driver exports the info through debugfs and likewise adds debugfs files
> for the reset- and wake-source info / registers.
>
> Despite this driver only exporting debugfs bits it is still useful to
> have this driver because it clears the wake- and reset-source registers
> after reading them. Not clearing these can have undesirable side-effects.
>
> Specifically if the WAKESRC register contains 0x01 (wake by powerbutton)
> on reboot then the firmware on some tablets turns the reboot into
> a poweroff. I guess this may be necessary to make long power-presses turn
> into a poweroff somehow?
>
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
I've added this to my review-hans (soon to be for-next) branch now.
Regards,
Hans
> ---
> drivers/platform/x86/intel/Kconfig | 10 ++
> drivers/platform/x86/intel/Makefile | 2 +
> drivers/platform/x86/intel/bytcrc_pwrsrc.c | 181 +++++++++++++++++++++
> 3 files changed, 193 insertions(+)
> create mode 100644 drivers/platform/x86/intel/bytcrc_pwrsrc.c
>
> diff --git a/drivers/platform/x86/intel/Kconfig b/drivers/platform/x86/intel/Kconfig
> index bbbd9e54e9ee..e9dc0c021029 100644
> --- a/drivers/platform/x86/intel/Kconfig
> +++ b/drivers/platform/x86/intel/Kconfig
> @@ -80,6 +80,16 @@ config INTEL_BXTWC_PMIC_TMU
> This driver enables the alarm wakeup functionality in the TMU unit of
> Whiskey Cove PMIC.
>
> +config INTEL_BYTCRC_PWRSRC
> + tristate "Intel Bay Trail Crystal Cove power source driver"
> + depends on INTEL_SOC_PMIC
> + help
> + This option adds a power source driver for Crystal Cove PMICs
> + on Intel Bay Trail devices.
> +
> + To compile this driver as a module, choose M here: the module
> + will be called intel_bytcrc_pwrsrc.
> +
> config INTEL_CHTDC_TI_PWRBTN
> tristate "Intel Cherry Trail Dollar Cove TI power button driver"
> depends on INTEL_SOC_PMIC_CHTDC_TI
> diff --git a/drivers/platform/x86/intel/Makefile b/drivers/platform/x86/intel/Makefile
> index 411df4040427..c1d5fe05e3f3 100644
> --- a/drivers/platform/x86/intel/Makefile
> +++ b/drivers/platform/x86/intel/Makefile
> @@ -38,6 +38,8 @@ intel_bxtwc_tmu-y := bxtwc_tmu.o
> obj-$(CONFIG_INTEL_BXTWC_PMIC_TMU) += intel_bxtwc_tmu.o
> intel_crystal_cove_charger-y := crystal_cove_charger.o
> obj-$(CONFIG_X86_ANDROID_TABLETS) += intel_crystal_cove_charger.o
> +intel_bytcrc_pwrsrc-y := bytcrc_pwrsrc.o
> +obj-$(CONFIG_INTEL_BYTCRC_PWRSRC) += intel_bytcrc_pwrsrc.o
> intel_chtdc_ti_pwrbtn-y := chtdc_ti_pwrbtn.o
> obj-$(CONFIG_INTEL_CHTDC_TI_PWRBTN) += intel_chtdc_ti_pwrbtn.o
> intel_chtwc_int33fe-y := chtwc_int33fe.o
> diff --git a/drivers/platform/x86/intel/bytcrc_pwrsrc.c b/drivers/platform/x86/intel/bytcrc_pwrsrc.c
> new file mode 100644
> index 000000000000..8a022b90d12d
> --- /dev/null
> +++ b/drivers/platform/x86/intel/bytcrc_pwrsrc.c
> @@ -0,0 +1,181 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Power-source driver for Bay Trail Crystal Cove PMIC
> + *
> + * Copyright (c) 2023 Hans de Goede <hdegoede@xxxxxxxxxx>
> + *
> + * Based on intel_crystalcove_pwrsrc.c from Android kernel sources, which is:
> + * Copyright (C) 2013 Intel Corporation
> + */
> +
> +#include <linux/debugfs.h>
> +#include <linux/mfd/intel_soc_pmic.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +#define CRYSTALCOVE_SPWRSRC_REG 0x1E
> +#define CRYSTALCOVE_RESETSRC0_REG 0x20
> +#define CRYSTALCOVE_RESETSRC1_REG 0x21
> +#define CRYSTALCOVE_WAKESRC_REG 0x22
> +
> +struct crc_pwrsrc_data {
> + struct regmap *regmap;
> + struct dentry *debug_dentry;
> + unsigned int resetsrc0;
> + unsigned int resetsrc1;
> + unsigned int wakesrc;
> +};
> +
> +static const char * const pwrsrc_pwrsrc_info[] = {
> + /* bit 0 */ "USB",
> + /* bit 1 */ "DC in",
> + /* bit 2 */ "Battery",
> + NULL,
> +};
> +
> +static const char * const pwrsrc_resetsrc0_info[] = {
> + /* bit 0 */ "SOC reporting a thermal event",
> + /* bit 1 */ "critical PMIC temperature",
> + /* bit 2 */ "critical system temperature",
> + /* bit 3 */ "critical battery temperature",
> + /* bit 4 */ "VSYS under voltage",
> + /* bit 5 */ "VSYS over voltage",
> + /* bit 6 */ "battery removal",
> + NULL,
> +};
> +
> +static const char * const pwrsrc_resetsrc1_info[] = {
> + /* bit 0 */ "VCRIT threshold",
> + /* bit 1 */ "BATID reporting battery removal",
> + /* bit 2 */ "user pressing the power button",
> + NULL,
> +};
> +
> +static const char * const pwrsrc_wakesrc_info[] = {
> + /* bit 0 */ "user pressing the power button",
> + /* bit 1 */ "a battery insertion",
> + /* bit 2 */ "a USB charger insertion",
> + /* bit 3 */ "an adapter insertion",
> + NULL,
> +};
> +
> +static void crc_pwrsrc_log(struct seq_file *seq, const char *prefix,
> + const char * const *info, unsigned int reg_val)
> +{
> + int i;
> +
> + for (i = 0; info[i]; i++) {
> + if (reg_val & BIT(i))
> + seq_printf(seq, "%s by %s\n", prefix, info[i]);
> + }
> +}
> +
> +static int pwrsrc_show(struct seq_file *seq, void *unused)
> +{
> + struct crc_pwrsrc_data *data = seq->private;
> + unsigned int reg_val;
> + int ret;
> +
> + ret = regmap_read(data->regmap, CRYSTALCOVE_SPWRSRC_REG, ®_val);
> + if (ret)
> + return ret;
> +
> + crc_pwrsrc_log(seq, "System powered", pwrsrc_pwrsrc_info, reg_val);
> + return 0;
> +}
> +
> +static int resetsrc_show(struct seq_file *seq, void *unused)
> +{
> + struct crc_pwrsrc_data *data = seq->private;
> +
> + crc_pwrsrc_log(seq, "Last shutdown caused", pwrsrc_resetsrc0_info, data->resetsrc0);
> + crc_pwrsrc_log(seq, "Last shutdown caused", pwrsrc_resetsrc1_info, data->resetsrc1);
> + return 0;
> +}
> +
> +static int wakesrc_show(struct seq_file *seq, void *unused)
> +{
> + struct crc_pwrsrc_data *data = seq->private;
> +
> + crc_pwrsrc_log(seq, "Last wake caused", pwrsrc_wakesrc_info, data->wakesrc);
> + return 0;
> +}
> +
> +DEFINE_SHOW_ATTRIBUTE(pwrsrc);
> +DEFINE_SHOW_ATTRIBUTE(resetsrc);
> +DEFINE_SHOW_ATTRIBUTE(wakesrc);
> +
> +static int crc_pwrsrc_read_and_clear(struct crc_pwrsrc_data *data,
> + unsigned int reg, unsigned int *val)
> +{
> + int ret;
> +
> + ret = regmap_read(data->regmap, reg, val);
> + if (ret)
> + return ret;
> +
> + return regmap_write(data->regmap, reg, *val);
> +}
> +
> +static int crc_pwrsrc_probe(struct platform_device *pdev)
> +{
> + struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent);
> + struct crc_pwrsrc_data *data;
> + int ret;
> +
> + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + data->regmap = pmic->regmap;
> +
> + /*
> + * Read + clear resetsrc0/1 and wakesrc now, so that they get
> + * cleared even if the debugfs interface is never used.
> + *
> + * Properly clearing the wakesrc is important, leaving bit 0 of it
> + * set turns reboot into poweroff on some tablets.
> + */
> + ret = crc_pwrsrc_read_and_clear(data, CRYSTALCOVE_RESETSRC0_REG, &data->resetsrc0);
> + if (ret)
> + return ret;
> +
> + ret = crc_pwrsrc_read_and_clear(data, CRYSTALCOVE_RESETSRC1_REG, &data->resetsrc1);
> + if (ret)
> + return ret;
> +
> + ret = crc_pwrsrc_read_and_clear(data, CRYSTALCOVE_WAKESRC_REG, &data->wakesrc);
> + if (ret)
> + return ret;
> +
> + data->debug_dentry = debugfs_create_dir(KBUILD_MODNAME, NULL);
> + debugfs_create_file("pwrsrc", 0444, data->debug_dentry, data, &pwrsrc_fops);
> + debugfs_create_file("resetsrc", 0444, data->debug_dentry, data, &resetsrc_fops);
> + debugfs_create_file("wakesrc", 0444, data->debug_dentry, data, &wakesrc_fops);
> +
> + platform_set_drvdata(pdev, data);
> + return 0;
> +}
> +
> +static int crc_pwrsrc_remove(struct platform_device *pdev)
> +{
> + struct crc_pwrsrc_data *data = platform_get_drvdata(pdev);
> +
> + debugfs_remove_recursive(data->debug_dentry);
> + return 0;
> +}
> +
> +static struct platform_driver crc_pwrsrc_driver = {
> + .probe = crc_pwrsrc_probe,
> + .remove = crc_pwrsrc_remove,
> + .driver = {
> + .name = "crystal_cove_pwrsrc",
> + },
> +};
> +module_platform_driver(crc_pwrsrc_driver);
> +
> +MODULE_ALIAS("platform:crystal_cove_pwrsrc");
> +MODULE_AUTHOR("Hans de Goede <hdegoede@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("Power-source driver for Bay Trail Crystal Cove PMIC");
> +MODULE_LICENSE("GPL");
