As some more information is added to the PCR register, we'd better use a copy of its content and modify just the peripheral-related bits. Implement a read-modify-write for the enable() and disable() callbacks.
Signed-off-by: Nicolas Ferre <[email protected]> --- v2: - modify header file beforehand so that we can use consistent field naming drivers/clk/at91/clk-peripheral.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/clk/at91/clk-peripheral.c b/drivers/clk/at91/clk-peripheral.c index 61d0adda7088..1e7dcc57925a 100644 --- a/drivers/clk/at91/clk-peripheral.c +++ b/drivers/clk/at91/clk-peripheral.c @@ -161,14 +161,18 @@ static int clk_sam9x5_peripheral_enable(struct clk_hw *hw) { struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); struct at91_pmc *pmc = periph->pmc; + u32 tmp; if (periph->id < PERIPHERAL_ID_MIN) return 0; - pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID_MASK) | - AT91_PMC_PCR_CMD | - AT91_PMC_PCR_DIV(periph->div) | - AT91_PMC_PCR_EN); + pmc_lock(pmc); + pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID_MASK)); + tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_DIV_MASK; + pmc_write(pmc, AT91_PMC_PCR, tmp | AT91_PMC_PCR_DIV(periph->div) + | AT91_PMC_PCR_CMD + | AT91_PMC_PCR_EN); + pmc_unlock(pmc); return 0; } @@ -176,12 +180,16 @@ static void clk_sam9x5_peripheral_disable(struct clk_hw *hw) { struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); struct at91_pmc *pmc = periph->pmc; + u32 tmp; if (periph->id < PERIPHERAL_ID_MIN) return; - pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID_MASK) | - AT91_PMC_PCR_CMD); + pmc_lock(pmc); + pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID_MASK)); + tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_EN; + pmc_write(pmc, AT91_PMC_PCR, tmp | AT91_PMC_PCR_CMD); + pmc_unlock(pmc); } static int clk_sam9x5_peripheral_is_enabled(struct clk_hw *hw) -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
