diff options
Diffstat (limited to 'drivers/clk/clk-si5351.c')
| -rw-r--r-- | drivers/clk/clk-si5351.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/clk/clk-si5351.c b/drivers/clk/clk-si5351.c index f63fcc0d8cf5..79b770fabe05 100644 --- a/drivers/clk/clk-si5351.c +++ b/drivers/clk/clk-si5351.c @@ -903,13 +903,42 @@ static int _si5351_clkout_set_disable_state( return 0; } +void _si5351_clkout_reset_pll(struct si5351_driver_data *drvdata, int num) +{ + u8 val = si5351_reg_read(drvdata, SI5351_CLK0_CTRL + num); + + switch (val & SI5351_CLK_INPUT_MASK) { + case SI5351_CLK_INPUT_XTAL: + case SI5351_CLK_INPUT_CLKIN: + return; /* pll not used, no need to reset */ + } + + si5351_reg_write(drvdata, SI5351_PLL_RESET, + val & SI5351_CLK_PLL_SELECT ? SI5351_PLL_RESET_B : + SI5351_PLL_RESET_A); + + dev_dbg(&drvdata->client->dev, "%s - %s: pll = %d\n", + __func__, clk_hw_get_name(&drvdata->clkout[num].hw), + (val & SI5351_CLK_PLL_SELECT) ? 1 : 0); +} + static int si5351_clkout_prepare(struct clk_hw *hw) { struct si5351_hw_data *hwdata = container_of(hw, struct si5351_hw_data, hw); + struct si5351_platform_data *pdata = + hwdata->drvdata->client->dev.platform_data; si5351_set_bits(hwdata->drvdata, SI5351_CLK0_CTRL + hwdata->num, SI5351_CLK_POWERDOWN, 0); + + /* + * Do a pll soft reset on the parent pll -- needed to get a + * deterministic phase relationship between the output clocks. + */ + if (pdata->clkout[hwdata->num].pll_reset) + _si5351_clkout_reset_pll(hwdata->drvdata, hwdata->num); + si5351_set_bits(hwdata->drvdata, SI5351_OUTPUT_ENABLE_CTRL, (1 << hwdata->num), 0); return 0; |