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path: root/drivers/clk/clk-twl6040.c
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Diffstat (limited to 'drivers/clk/clk-twl6040.c')
-rw-r--r--drivers/clk/clk-twl6040.c53
1 files changed, 51 insertions, 2 deletions
diff --git a/drivers/clk/clk-twl6040.c b/drivers/clk/clk-twl6040.c
index ea846f77750b..0cad5748bf0e 100644
--- a/drivers/clk/clk-twl6040.c
+++ b/drivers/clk/clk-twl6040.c
@@ -41,6 +41,43 @@ static int twl6040_pdmclk_is_prepared(struct clk_hw *hw)
return pdmclk->enabled;
}
+static int twl6040_pdmclk_reset_one_clock(struct twl6040_pdmclk *pdmclk,
+ unsigned int reg)
+{
+ const u8 reset_mask = TWL6040_HPLLRST; /* Same for HPPLL and LPPLL */
+ int ret;
+
+ ret = twl6040_set_bits(pdmclk->twl6040, reg, reset_mask);
+ if (ret < 0)
+ return ret;
+
+ ret = twl6040_clear_bits(pdmclk->twl6040, reg, reset_mask);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+/*
+ * TWL6040A2 Phoenix Audio IC erratum #6: "PDM Clock Generation Issue At
+ * Cold Temperature". This affects cold boot and deeper idle states it
+ * seems. The workaround consists of resetting HPPLL and LPPLL.
+ */
+static int twl6040_pdmclk_quirk_reset_clocks(struct twl6040_pdmclk *pdmclk)
+{
+ int ret;
+
+ ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_HPPLLCTL);
+ if (ret)
+ return ret;
+
+ ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_LPPLLCTL);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
static int twl6040_pdmclk_prepare(struct clk_hw *hw)
{
struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk,
@@ -48,8 +85,20 @@ static int twl6040_pdmclk_prepare(struct clk_hw *hw)
int ret;
ret = twl6040_power(pdmclk->twl6040, 1);
- if (!ret)
- pdmclk->enabled = 1;
+ if (ret)
+ return ret;
+
+ ret = twl6040_pdmclk_quirk_reset_clocks(pdmclk);
+ if (ret)
+ goto out_err;
+
+ pdmclk->enabled = 1;
+
+ return 0;
+
+out_err:
+ dev_err(pdmclk->dev, "%s: error %i\n", __func__, ret);
+ twl6040_power(pdmclk->twl6040, 0);
return ret;
}