diff options
| -rw-r--r-- | drivers/clk/bcm/clk-bcm2835.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c index 7a35df6b45bd..8ee0f0b28ea3 100644 --- a/drivers/clk/bcm/clk-bcm2835.c +++ b/drivers/clk/bcm/clk-bcm2835.c @@ -1518,6 +1518,31 @@ static const char *const bcm2835_clock_per_parents[] = { .parents = bcm2835_clock_per_parents, \ __VA_ARGS__) +/* + * Restrict clock sources for the PCM peripheral to the oscillator and + * PLLD_PER because other source may have varying rates or be switched + * off. + * + * Prevent other sources from being selected by replacing their names in + * the list of potential parents with dummy entries (entry index is + * significant). + */ +static const char *const bcm2835_pcm_per_parents[] = { + "-", + "xosc", + "-", + "-", + "-", + "-", + "plld_per", + "-", +}; + +#define REGISTER_PCM_CLK(...) REGISTER_CLK( \ + .num_mux_parents = ARRAY_SIZE(bcm2835_pcm_per_parents), \ + .parents = bcm2835_pcm_per_parents, \ + __VA_ARGS__) + /* main vpu parent mux */ static const char *const bcm2835_clock_vpu_parents[] = { "gnd", @@ -1995,7 +2020,7 @@ static const struct bcm2835_clk_desc clk_desc_array[] = { .int_bits = 4, .frac_bits = 8, .tcnt_mux = 22), - [BCM2835_CLOCK_PCM] = REGISTER_PER_CLK( + [BCM2835_CLOCK_PCM] = REGISTER_PCM_CLK( .name = "pcm", .ctl_reg = CM_PCMCTL, .div_reg = CM_PCMDIV, |