| From 3fd0f3b5109a72fcfa895d8820abbe5ed4b9aeba Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Tue, 30 Mar 2021 12:12:34 +0100 |
| Subject: drivers: nvmem: Fix voltage settings for QTI qfprom-efuse |
| |
| From: Ravi Kumar Bokka <rbokka@codeaurora.org> |
| |
| [ Upstream commit 9ec4f4b0e9fd3ad4b9a38bddb75b516ea09f4628 ] |
| |
| QFPROM controller hardware requires 1.8V min for fuse blowing. |
| So, this change sets the voltage to 1.8V, required to blow the fuse |
| for qfprom-efuse controller. |
| |
| To disable fuse blowing, we set the voltage to 0V since this may |
| be a shared rail and may be able to run at a lower rate when we're |
| not blowing fuses. |
| |
| Fixes: 93b4e49f8c86 ("nvmem: qfprom: Add fuse blowing support") |
| Reported-by: Douglas Anderson <dianders@chromium.org> |
| Suggested-by: Douglas Anderson <dianders@chromium.org> |
| Reviewed-by: Douglas Anderson <dianders@chromium.org> |
| Signed-off-by: Ravi Kumar Bokka <rbokka@codeaurora.org> |
| Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> |
| Link: https://lore.kernel.org/r/20210330111241.19401-4-srinivas.kandagatla@linaro.org |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/nvmem/qfprom.c | 21 +++++++++++++++++++++ |
| 1 file changed, 21 insertions(+) |
| |
| diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c |
| index 6cace24dfbf7..100d69d8f2e1 100644 |
| --- a/drivers/nvmem/qfprom.c |
| +++ b/drivers/nvmem/qfprom.c |
| @@ -127,6 +127,16 @@ static void qfprom_disable_fuse_blowing(const struct qfprom_priv *priv, |
| { |
| int ret; |
| |
| + /* |
| + * This may be a shared rail and may be able to run at a lower rate |
| + * when we're not blowing fuses. At the moment, the regulator framework |
| + * applies voltage constraints even on disabled rails, so remove our |
| + * constraints and allow the rail to be adjusted by other users. |
| + */ |
| + ret = regulator_set_voltage(priv->vcc, 0, INT_MAX); |
| + if (ret) |
| + dev_warn(priv->dev, "Failed to set 0 voltage (ignoring)\n"); |
| + |
| ret = regulator_disable(priv->vcc); |
| if (ret) |
| dev_warn(priv->dev, "Failed to disable regulator (ignoring)\n"); |
| @@ -172,6 +182,17 @@ static int qfprom_enable_fuse_blowing(const struct qfprom_priv *priv, |
| goto err_clk_prepared; |
| } |
| |
| + /* |
| + * Hardware requires 1.8V min for fuse blowing; this may be |
| + * a rail shared do don't specify a max--regulator constraints |
| + * will handle. |
| + */ |
| + ret = regulator_set_voltage(priv->vcc, 1800000, INT_MAX); |
| + if (ret) { |
| + dev_err(priv->dev, "Failed to set 1.8 voltage\n"); |
| + goto err_clk_rate_set; |
| + } |
| + |
| ret = regulator_enable(priv->vcc); |
| if (ret) { |
| dev_err(priv->dev, "Failed to enable regulator\n"); |
| -- |
| 2.30.2 |
| |