From patchwork Wed Jun 3 13:36:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dario Binacchi X-Patchwork-Id: 241612 List-Id: U-Boot discussion From: dariobin at libero.it (Dario Binacchi) Date: Wed, 3 Jun 2020 15:36:25 +0200 Subject: [PATCH 1/1] clk: ccf: mux: change the get_rate helper Message-ID: <20200603133625.6597-1-dariobin@libero.it> The previous version of the get_rate helper does not work if the mux clock parent is changed after the probe. This error has not been detected because this condition has not been tested. The error occurs because the set_parent helper does not change the parent of the clock device but only the clock selection register. Since changing the parent of a probed device can be tricky, the new version of the get_rate helper provides the rate of the selected clock and not that of the parent. Signed-off-by: Dario Binacchi --- drivers/clk/clk-mux.c | 26 +++++++++++++++++++++++++- test/dm/clk_ccf.c | 24 ++++++++++++++++++++++++ 2 files changed, 49 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c index 8f85e84ae9..1f2dab647f 100644 --- a/drivers/clk/clk-mux.c +++ b/drivers/clk/clk-mux.c @@ -152,8 +152,32 @@ static int clk_mux_set_parent(struct clk *clk, struct clk *parent) return 0; } +static ulong clk_mux_get_rate(struct clk *clk) +{ + struct clk_mux *mux = to_clk_mux(clk_dev_binded(clk) ? + dev_get_clk_ptr(clk->dev) : clk); + struct udevice *parent; + struct clk *pclk; + int err, index; + + index = clk_mux_get_parent(clk); + if (index >= mux->num_parents) + return -EFAULT; + + err = uclass_get_device_by_name(UCLASS_CLK, mux->parent_names[index], + &parent); + if (err) + return err; + + pclk = dev_get_clk_ptr(parent); + if (!pclk) + return -ENODEV; + + return clk_get_rate(pclk); +} + const struct clk_ops clk_mux_ops = { - .get_rate = clk_generic_get_rate, + .get_rate = clk_mux_get_rate, .set_parent = clk_mux_set_parent, }; diff --git a/test/dm/clk_ccf.c b/test/dm/clk_ccf.c index ae3a4d8a76..bf99776ac1 100644 --- a/test/dm/clk_ccf.c +++ b/test/dm/clk_ccf.c @@ -46,6 +46,18 @@ static int dm_test_clk_ccf(struct unit_test_state *uts) rate = clk_get_parent_rate(clk); ut_asserteq(rate, 60000000); + rate = clk_get_rate(clk); + ut_asserteq(rate, 60000000); + + ret = clk_get_by_id(SANDBOX_CLK_PLL3_80M, &pclk); + ut_assertok(ret); + + ret = clk_set_parent(clk, pclk); + ut_assertok(ret); + + rate = clk_get_rate(clk); + ut_asserteq(rate, 80000000); + ret = clk_get_by_id(SANDBOX_CLK_USDHC2_SEL, &clk); ut_assertok(ret); ut_asserteq_str("usdhc2_sel", clk->dev->name); @@ -56,6 +68,18 @@ static int dm_test_clk_ccf(struct unit_test_state *uts) pclk = clk_get_parent(clk); ut_asserteq_str("pll3_80m", pclk->dev->name); + rate = clk_get_rate(clk); + ut_asserteq(rate, 80000000); + + ret = clk_get_by_id(SANDBOX_CLK_PLL3_60M, &pclk); + ut_assertok(ret); + + ret = clk_set_parent(clk, pclk); + ut_assertok(ret); + + rate = clk_get_rate(clk); + ut_asserteq(rate, 60000000); + /* Test the composite of CCF */ ret = clk_get_by_id(SANDBOX_CLK_I2C, &clk); ut_assertok(ret);