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Commit 86dbfda83215e340445a0ae44e24c84031e79f1c

Authored by Martin Sperl
Committed by Greg Kroah-Hartman
1 parent 035688290a
Exists in smarct4x-processor-sdk-linux-03.00.00.04 and in 2 other branches dlt-processor-sdk-linux-03.00.00.04, smarct3x-processor-sdk-linux-03.00.00.04

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>

Showing 1 changed file with 4 additions and 0 deletions Side-by-side Diff

drivers/clk/bcm/clk-bcm2835.c
Diff comments   View file @ 86dbfda
... ... @@ -1068,10 +1068,12 @@
1068 1068 struct bcm2835_cprman *cprman = divider->cprman;
1069 1069 const struct bcm2835_pll_divider_data *data = divider->data;
1070 1070  
  1071 + spin_lock(&cprman->regs_lock);
1071 1072 cprman_write(cprman, data->cm_reg,
1072 1073 (cprman_read(cprman, data->cm_reg) &
1073 1074 ~data->load_mask) | data->hold_mask);
1074 1075 cprman_write(cprman, data->a2w_reg, A2W_PLL_CHANNEL_DISABLE);
  1076 + spin_unlock(&cprman->regs_lock);
1075 1077 }
1076 1078  
1077 1079 static int bcm2835_pll_divider_on(struct clk_hw *hw)
1078 1080  
... ... @@ -1080,12 +1082,14 @@
1080 1082 struct bcm2835_cprman *cprman = divider->cprman;
1081 1083 const struct bcm2835_pll_divider_data *data = divider->data;
1082 1084  
  1085 + spin_lock(&cprman->regs_lock);
1083 1086 cprman_write(cprman, data->a2w_reg,
1084 1087 cprman_read(cprman, data->a2w_reg) &
1085 1088 ~A2W_PLL_CHANNEL_DISABLE);
1086 1089  
1087 1090 cprman_write(cprman, data->cm_reg,
1088 1091 cprman_read(cprman, data->cm_reg) & ~data->hold_mask);
  1092 + spin_unlock(&cprman->regs_lock);
1089 1093  
1090 1094 return 0;
1091 1095 }