The patch regulator: twl6030: workaround the VMMC reset behavior has been applied to the regulator tree at https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-5.4 All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From d9df0187b6edd5871255cee29128c63f134e599c Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx> Date: Thu, 25 Jul 2019 11:45:42 +0200 Subject: [PATCH] regulator: twl6030: workaround the VMMC reset behavior During reset the VMMC regulator doesn't reach 0V and only drops to 1.8V, furthermore the pulse width is under 200us whereas the SD specification expect 1ms. The WR_S bit allows the TWL6030 to no reset at all the VMMC during warm reset and keep the current voltage. Thanks to this workaround the SD card doesn't reach a undefined reset stage. Actually this behavior is available for all the LDO regulator, so the driver will also allow to use it with any of these regulator. Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20190725094542.16547-4-gregory.clement@xxxxxxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- drivers/regulator/twl6030-regulator.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/regulator/twl6030-regulator.c b/drivers/regulator/twl6030-regulator.c index d73c81542ceb..b8100c3cedad 100644 --- a/drivers/regulator/twl6030-regulator.c +++ b/drivers/regulator/twl6030-regulator.c @@ -57,6 +57,9 @@ struct twlreg_info { #define VREG_BC_PROC 3 #define VREG_BC_CLK_RST 4 +/* TWL6030 LDO register values for VREG_VOLTAGE */ +#define TWL6030_VREG_VOLTAGE_WR_S BIT(7) + /* TWL6030 LDO register values for CFG_STATE */ #define TWL6030_CFG_STATE_OFF 0x00 #define TWL6030_CFG_STATE_ON 0x01 @@ -68,9 +71,10 @@ struct twlreg_info { #define TWL6030_CFG_STATE_APP(v) (((v) & TWL6030_CFG_STATE_APP_MASK) >>\ TWL6030_CFG_STATE_APP_SHIFT) -/* Flags for SMPS Voltage reading */ +/* Flags for SMPS Voltage reading and LDO reading*/ #define SMPS_OFFSET_EN BIT(0) #define SMPS_EXTENDED_EN BIT(1) +#define TWL_6030_WARM_RESET BIT(3) /* twl6032 SMPS EPROM values */ #define TWL6030_SMPS_OFFSET 0xB0 @@ -250,6 +254,9 @@ twl6030ldo_set_voltage_sel(struct regulator_dev *rdev, unsigned selector) { struct twlreg_info *info = rdev_get_drvdata(rdev); + if (info->flags & TWL_6030_WARM_RESET) + selector |= TWL6030_VREG_VOLTAGE_WR_S; + return twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE, selector); } @@ -259,6 +266,9 @@ static int twl6030ldo_get_voltage_sel(struct regulator_dev *rdev) struct twlreg_info *info = rdev_get_drvdata(rdev); int vsel = twlreg_read(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE); + if (info->flags & TWL_6030_WARM_RESET) + vsel &= ~TWL6030_VREG_VOLTAGE_WR_S; + return vsel; } @@ -710,6 +720,9 @@ static int twlreg_probe(struct platform_device *pdev) break; } + if (of_get_property(np, "ti,retain-on-reset", NULL)) + info->flags |= TWL_6030_WARM_RESET; + config.dev = &pdev->dev; config.init_data = initdata; config.driver_data = info; -- 2.20.1
