[U-Boot] [PATCH 22/55] dm: power: Add support for TPS65090 FETs

[Przemyslaw Marczak <p.marczak@samsung.com>]

Hello Simon,

On 07/03/2015 02:15 AM, Simon Glass wrote:
> The TPS65090 has 7 FETs which are modelled as regulators. This allows them
> to be controlled by drivers easier, accessed through the 'regulator' command
> and used by other drivers.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>   drivers/power/regulator/Kconfig              |  10 ++
>   drivers/power/regulator/Makefile             |   1 +
>   drivers/power/regulator/tps65090_regulator.c | 138 +++++++++++++++++++++++++++
>   3 files changed, 149 insertions(+)
>   create mode 100644 drivers/power/regulator/tps65090_regulator.c
>
> diff --git a/drivers/power/regulator/Kconfig b/drivers/power/regulator/Kconfig
> index 6289b83..d090650 100644
> --- a/drivers/power/regulator/Kconfig
> +++ b/drivers/power/regulator/Kconfig
> @@ -61,3 +61,13 @@ config DM_REGULATOR_SANDBOX
>
>   	A detailed information can be found in header: '<power/sandbox_pmic.h>'
>   	Binding info: 'doc/device-tree-bindings/pmic/max77686.txt'
> +
> +config REGULATOR_TPS65090
> +	bool "Enable driver for TPS65090 PMIC regulators"
> +	depends on PMIC_TPS65090
> +	---help---
> +	The TPS65090 provides several FETs (Field-effect Transistors,
> +	effectively switches) which are supported by this driver as
> +	regulators, one for each FET. The standard regulator interface is
> +	supported, but it is only possible to turn the regulators on or off.
> +	There is no voltage/current control.
> diff --git a/drivers/power/regulator/Makefile b/drivers/power/regulator/Makefile
> index 96aa624..43f4d2c 100644
> --- a/drivers/power/regulator/Makefile
> +++ b/drivers/power/regulator/Makefile
> @@ -9,3 +9,4 @@ obj-$(CONFIG_DM_REGULATOR) += regulator-uclass.o
>   obj-$(CONFIG_DM_REGULATOR_MAX77686) += max77686.o
>   obj-$(CONFIG_DM_REGULATOR_FIXED) += fixed.o
>   obj-$(CONFIG_DM_REGULATOR_SANDBOX) += sandbox.o
> +obj-$(CONFIG_REGULATOR_TPS65090) += tps65090_regulator.o
> diff --git a/drivers/power/regulator/tps65090_regulator.c b/drivers/power/regulator/tps65090_regulator.c
> new file mode 100644
> index 0000000..affc504
> --- /dev/null
> +++ b/drivers/power/regulator/tps65090_regulator.c
> @@ -0,0 +1,138 @@
> +/*
> + * Copyright (c) 2015 Google, Inc
> + *
> + * SPDX-License-Identifier:	GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <dm.h>
> +#include <errno.h>
> +#include <power/pmic.h>
> +#include <power/regulator.h>
> +#include <power/tps65090.h>
> +
> +static int tps65090_fet_probe(struct udevice *dev)
> +{
> +	struct dm_regulator_uclass_platdata *uc_pdata;
> +
> +	uc_pdata = dev_get_uclass_platdata(dev);
> +
> +	uc_pdata->type = REGULATOR_TYPE_OTHER;
> +	uc_pdata->mode_count = 0;
> +
> +	return 0;
> +}
> +
> +static bool tps65090_fet_get_enable(struct udevice *dev)
> +{
> +	struct udevice *pmic = dev_get_parent(dev);
> +	int ret, fet_id;
> +
> +	fet_id = dev->driver_data;
> +	debug("%s: fet_id=%d\n", __func__, fet_id);
> +
> +	ret = pmic_reg_read(pmic, REG_FET_BASE + fet_id);
> +	if (ret < 0)
> +		return ret;
> +
> +	return ret & FET_CTRL_ENFET;
> +}
> +
> +/**
> + * Set the power state for a FET
> + *
> + * @param pmic		pmic structure for the tps65090
> + * @param fet_id	FET number to set (1..MAX_FET_NUM)
> + * @param set		1 to power on FET, 0 to power off
> + * @return -EIO if we got a comms error, -EAGAIN if the FET failed to
> + * change state. If all is ok, returns 0.
> + */
> +static int tps65090_fet_set(struct udevice *pmic, int fet_id, bool set)
> +{
> +	int retry;
> +	u32 value;
> +	int ret;
> +
> +	value = FET_CTRL_ADENFET | FET_CTRL_WAIT;
> +	if (set)
> +		value |= FET_CTRL_ENFET;
> +
> +	if (pmic_reg_write(pmic, REG_FET_BASE + fet_id, value))
> +		return -EIO;
> +
> +	/* Try reading until we get a result */
> +	for (retry = 0; retry < MAX_CTRL_READ_TRIES; retry++) {
> +		ret = pmic_reg_read(pmic, REG_FET_BASE + fet_id);
> +		if (ret < 0)
> +			return ret;
> +
> +		/* Check that the FET went into the expected state */
> +		debug("%s: flags=%x\n", __func__, ret);
> +		if (!!(ret & FET_CTRL_PGFET) == set)
> +			return 0;
> +
> +		/* If we got a timeout, there is no point in waiting longer */
> +		if (ret & FET_CTRL_TOFET)
> +			break;
> +
> +		mdelay(1);
> +	}
> +
> +	debug("FET %d: Power good should have set to %d but reg=%#02x\n",
> +	      fet_id, set, ret);
> +	return -EAGAIN;
> +}
> +
> +static int tps65090_fet_set_enable(struct udevice *dev, bool enable)
> +{
> +	struct udevice *pmic = dev_get_parent(dev);
> +	int ret, fet_id;
> +	ulong start;
> +	int loops;
> +
> +	fet_id = dev->driver_data;
> +	debug("%s: fet_id=%d, enable=%d\n", __func__, fet_id, enable);
> +
> +	start = get_timer(0);
> +	for (loops = 0;; loops++) {
> +		ret = tps65090_fet_set(pmic, fet_id, enable);
> +		if (!ret)
> +			break;
> +
> +		if (get_timer(start) > 100)
> +			break;
> +
> +		/* Turn it off and try again until we time out */
> +		tps65090_fet_set(pmic, fet_id, false);
> +	}
> +
> +	if (ret)
> +		debug("%s: FET%d failed to power on: time=%lums, loops=%d\n",
> +		      __func__, fet_id, get_timer(start), loops);
> +	else if (loops)
> +		debug("%s: FET%d powered on after %lums, loops=%d\n",
> +		      __func__, fet_id, get_timer(start), loops);
> +
> +	/*
> +	 * Unfortunately there are some conditions where the power-good bit
> +	 * will be 0, but the FET still comes up. One such case occurs with
> +	 * the LCD backlight on snow. We'll just return 0 here and assume
> +	 * that the FET will eventually come up.
> +	 */
> +	if (ret == -EAGAIN)
> +		ret = 0;
> +
> +	return ret;
> +}
> +
> +static const struct dm_regulator_ops tps65090_fet_ops = {
> +	.get_enable = tps65090_fet_get_enable,
> +	.set_enable = tps65090_fet_set_enable,
> +};
> +
> +U_BOOT_DRIVER(tps65090_fet) = {
> +	.name = TPS65090_FET_DRIVER,
> +	.id = UCLASS_REGULATOR,
> +	.ops = &tps65090_fet_ops,
> +	.probe = tps65090_fet_probe,
> +};
>

Acked-by: Przemyslaw Marczak <p.marczak@samsung.com>

Regards
-- 
Przemyslaw Marczak
Samsung R&D Institute Poland
Samsung Electronics
p.marczak at samsung.com