This adds a helper function for clk_get_by_name in cases where the clock is optional. Hopefully this helps point driver writers in the right direction. Also convert some existing users.

Signed-off-by: Sean Anderson seanga2@gmail.com Reviewed-by: Neil Armstrong narmstrong@baylibre.com Reviewed-by: Simon Glass sjg@chromium.org ---

Changes in v3: - Fix clk_get_by_name_optional recursing

drivers/clk/clk_zynq.c | 5 +++-- drivers/rng/meson-rng.c | 4 ++-- include/clk.h | 24 ++++++++++++++++++++++++ 3 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/clk_zynq.c b/drivers/clk/clk_zynq.c index 18915c3e04..e80500e382 100644 --- a/drivers/clk/clk_zynq.c +++ b/drivers/clk/clk_zynq.c @@ -472,8 +472,9 @@ static int zynq_clk_probe(struct udevice *dev)

for (i = 0; i < 2; i++) { sprintf(name, "gem%d_emio_clk", i); - ret = clk_get_by_name(dev, name, &priv->gem_emio_clk[i]); - if (ret < 0 && ret != -ENODATA) { + ret = clk_get_by_name_optional(dev, name, + &priv->gem_emio_clk[i]); + if (ret) { dev_err(dev, "failed to get %s clock\n", name); return ret; } diff --git a/drivers/rng/meson-rng.c b/drivers/rng/meson-rng.c index 5a4f45ad5a..e0a1e8c7e0 100644 --- a/drivers/rng/meson-rng.c +++ b/drivers/rng/meson-rng.c @@ -91,8 +91,8 @@ static int meson_rng_of_to_plat(struct udevice *dev) return -ENODEV;

/* Get optional "core" clock */ - err = clk_get_by_name(dev, "core", &pdata->clk); - if (err && err != -ENODATA) + err = clk_get_by_name_optional(dev, "core", &pdata->clk); + if (err) return err;

return 0; diff --git a/include/clk.h b/include/clk.h index 33f448eb89..c30a5dba97 100644 --- a/include/clk.h +++ b/include/clk.h @@ -292,6 +292,30 @@ static inline int clk_release_all(struct clk *clk, int count) } #endif

+/** + * clk_get_by_name_optional() - Get/request a optional clock by name. + * @dev: The client device. + * @name: The name of the clock to request, within the client's list of + * clocks. + * @clk: A pointer to a clock struct to initialize. + * + * Behaves the same as clk_get_by_name(), except when there is no clock + * provider. In the latter case, return 0. + * + * Return: 0 if OK, or a negative error code. + */ +static inline int clk_get_by_name_optional(struct udevice *dev, + const char *name, struct clk *clk) +{ + int ret; + + ret = clk_get_by_name(dev, name, clk); + if (ret == -ENODATA) + return 0; + + return ret; +} + /** * clk_get_by_name_nodev_optional - Get/request an optinonal clock by name * without a device.