[PATCH v2 2/2] clk: bcm2835: Fix PLL poweron

Eric Anholt eric at anholt.net
Wed Apr 13 13:05:03 PDT 2016

In poweroff, we set the reset bit and the power down bit, but only
managed to unset the reset bit for poweron.  This meant that if HDMI
did -EPROBE_DEFER after it had grabbed its clocks, we'd power down the
PLLH (that had been on at boot time) and never recover.

Signed-off-by: Eric Anholt <eric at anholt.net>
Fixes: 41691b8862e2 ("clk: bcm2835: Add support for programming the audio domain clocks")
Cc: stable at vger.kernel.org

v2: add fixes tag

 drivers/clk/bcm/clk-bcm2835.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index 87616ded5bbe..7a7970865c2d 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -554,6 +554,10 @@ static int bcm2835_pll_on(struct clk_hw *hw)
 	const struct bcm2835_pll_data *data = pll->data;
 	ktime_t timeout;
+	cprman_write(cprman, data->a2w_ctrl_reg,
+		     cprman_read(cprman, data->a2w_ctrl_reg) &
+		     ~A2W_PLL_CTRL_PWRDN);
 	/* Take the PLL out of reset. */
 	cprman_write(cprman, data->cm_ctrl_reg,
 		     cprman_read(cprman, data->cm_ctrl_reg) & ~CM_PLL_ANARST);

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