diff options
| author | Martin Sperl <kernel@martin.sperl.org> | 2016-02-29 11:39:18 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-06-01 12:15:53 -0700 |
| commit | 86dbfda83215e340445a0ae44e24c84031e79f1c (patch) | |
| tree | b3ef5804420b5cfbb2dd4703576217cefdff2015 | |
| parent | 035688290a740745adf9daff65bceac8b70e8732 (diff) | |
| download | lwn-86dbfda83215e340445a0ae44e24c84031e79f1c.tar.gz lwn-86dbfda83215e340445a0ae44e24c84031e79f1c.zip | |
clk: bcm2835: add locking to pll*_on/off methods
commit ec36a5c6682fdd5328abf15c3c67281bed0241d7 upstream.
Add missing locking to:
* bcm2835_pll_divider_on
* bcm2835_pll_divider_off
to protect the read modify write cycle for the
register access protecting both cm_reg and a2w_reg
registers.
Fixes: 41691b8862e2 ("clk: bcm2835: Add support for programming the
audio domain clocks")
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/clk/bcm/clk-bcm2835.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c index 4f9830c1b121..185a4d859638 100644 --- a/drivers/clk/bcm/clk-bcm2835.c +++ b/drivers/clk/bcm/clk-bcm2835.c @@ -1068,10 +1068,12 @@ static void bcm2835_pll_divider_off(struct clk_hw *hw) struct bcm2835_cprman *cprman = divider->cprman; const struct bcm2835_pll_divider_data *data = divider->data; + spin_lock(&cprman->regs_lock); cprman_write(cprman, data->cm_reg, (cprman_read(cprman, data->cm_reg) & ~data->load_mask) | data->hold_mask); cprman_write(cprman, data->a2w_reg, A2W_PLL_CHANNEL_DISABLE); + spin_unlock(&cprman->regs_lock); } static int bcm2835_pll_divider_on(struct clk_hw *hw) @@ -1080,12 +1082,14 @@ static int bcm2835_pll_divider_on(struct clk_hw *hw) struct bcm2835_cprman *cprman = divider->cprman; const struct bcm2835_pll_divider_data *data = divider->data; + spin_lock(&cprman->regs_lock); cprman_write(cprman, data->a2w_reg, cprman_read(cprman, data->a2w_reg) & ~A2W_PLL_CHANNEL_DISABLE); cprman_write(cprman, data->cm_reg, cprman_read(cprman, data->cm_reg) & ~data->hold_mask); + spin_unlock(&cprman->regs_lock); return 0; } |