diff options
Diffstat (limited to '0098-i2c-designware-Use-standard-optional-ref-clock-imple.patch')
| -rw-r--r-- | 0098-i2c-designware-Use-standard-optional-ref-clock-imple.patch | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/0098-i2c-designware-Use-standard-optional-ref-clock-imple.patch b/0098-i2c-designware-Use-standard-optional-ref-clock-imple.patch new file mode 100644 index 000000000000..90add044f51c --- /dev/null +++ b/0098-i2c-designware-Use-standard-optional-ref-clock-imple.patch @@ -0,0 +1,76 @@ +From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 +From: Serge Semin <Sergey.Semin@baikalelectronics.ru> +Date: Fri, 10 Jun 2022 10:42:33 +0300 +Subject: [PATCH] i2c: designware: Use standard optional ref clock + implementation + +[ Upstream commit 27071b5cbca59d8e8f8750c199a6cbf8c9799963 ] + +Even though the DW I2C controller reference clock source is requested by +the method devm_clk_get() with non-optional clock requirement the way the +clock handler is used afterwards has a pure optional clock semantic +(though in some circumstances we can get a warning about the clock missing +printed in the system console). There is no point in reimplementing that +functionality seeing the kernel clock framework already supports the +optional interface from scratch. Thus let's convert the platform driver to +using it. + +Note by providing this commit we get to fix two problems. The first one +was introduced in commit c62ebb3d5f0d ("i2c: designware: Add support for +an interface clock"). It causes not having the interface clock (pclk) +enabled/disabled in case if the reference clock isn't provided. The second +problem was first introduced in commit b33af11de236 ("i2c: designware: Do +not require clock when SSCN and FFCN are provided"). Since that +modification the deferred probe procedure has been unsupported in case if +the interface clock isn't ready. + +Fixes: c62ebb3d5f0d ("i2c: designware: Add support for an interface clock") +Fixes: b33af11de236 ("i2c: designware: Do not require clock when SSCN and FFCN are provided") +Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> +Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> +Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> +Signed-off-by: Wolfram Sang <wsa@kernel.org> +Signed-off-by: Sasha Levin <sashal@kernel.org> +--- + drivers/i2c/busses/i2c-designware-common.c | 3 --- + drivers/i2c/busses/i2c-designware-platdrv.c | 13 +++++++++++-- + 2 files changed, 11 insertions(+), 5 deletions(-) + +diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c +index 9f8574320eb2dfe3b4bf51bac51b9664e61afa4b..b08e5bc2b64ccca5cf069cbd605e63bff08cb945 100644 +--- a/drivers/i2c/busses/i2c-designware-common.c ++++ b/drivers/i2c/busses/i2c-designware-common.c +@@ -477,9 +477,6 @@ int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare) + { + int ret; + +- if (IS_ERR(dev->clk)) +- return PTR_ERR(dev->clk); +- + if (prepare) { + /* Optional interface clock */ + ret = clk_prepare_enable(dev->pclk); +diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c +index 70ade5306e458fdcdfaf53472195ecc24fafe40b..ba043b5473936b67f135b0d34c24efa2518cc12e 100644 +--- a/drivers/i2c/busses/i2c-designware-platdrv.c ++++ b/drivers/i2c/busses/i2c-designware-platdrv.c +@@ -320,8 +320,17 @@ static int dw_i2c_plat_probe(struct platform_device *pdev) + goto exit_reset; + } + +- dev->clk = devm_clk_get(&pdev->dev, NULL); +- if (!i2c_dw_prepare_clk(dev, true)) { ++ dev->clk = devm_clk_get_optional(&pdev->dev, NULL); ++ if (IS_ERR(dev->clk)) { ++ ret = PTR_ERR(dev->clk); ++ goto exit_reset; ++ } ++ ++ ret = i2c_dw_prepare_clk(dev, true); ++ if (ret) ++ goto exit_reset; ++ ++ if (dev->clk) { + u64 clk_khz; + + dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; |