[alsa-devel] [PATCH v2] ASoC: mxs-saif: add mclk enable/disable ops
Jörg Krause
joerg.krause at embedded.rocks
Sat Jan 7 18:23:48 CET 2017
Hi Mans,
On Thu, 2016-12-22 at 16:49 +0000, Mans Rullgard wrote:
> This makes normal clk_enable/disable() calls on mxs_saif_mclk work as
> expected, i.e. actually turn the mclk output on or (when safe) off.
> The existing mxs_saif_get/put_mclk() functions are rewritten to use
> common clk operations on mxs_saif_mclk rather than accessing
> registers
> directly.
>
> With these changes mxs-saif can be used together with the simple-card
> driver.
I can confirm that this works for me using the pcm5102a, wm8524 and the
wm8731 codec driver. But I was able only to test playback on saif0 for
those drivers as I failed to setup the simple-card device tree node
both for saif0 and saif1.
However, when using this patch with a platform driver, e.g. mxs-wm8524,
instead of the simple-card device tree node configuration, it fails for
me. Note, that the platform driver mxs-wm8524 is just a mere copy of
the mxs-sgtl5000 driver. The error happens when probing the platform
driver at calling mxs_saif_get_mclk(): "failed to get mclk".
As I am testing on a custom board not mainlined yet it is possible that
I did something wrong. So maybe someone having access to a mxs-board
with a sgtl5000 codec can verify this?
Jörg
>
> Signed-off-by: Mans Rullgard <mans at mansr.com>
> ---
> v2: add #include <linux/clk-provider.h> needed by some configs
> ---
> sound/soc/mxs/mxs-saif.c | 144 +++++++++++++++++++++++++++++++----
> ------------
> sound/soc/mxs/mxs-saif.h | 3 +
> 2 files changed, 99 insertions(+), 48 deletions(-)
>
> diff --git a/sound/soc/mxs/mxs-saif.c b/sound/soc/mxs/mxs-saif.c
> index a002ab892772..7c620399f96b 100644
> --- a/sound/soc/mxs/mxs-saif.c
> +++ b/sound/soc/mxs/mxs-saif.c
> @@ -204,27 +204,15 @@ static int mxs_saif_set_clk(struct mxs_saif
> *saif,
> */
> int mxs_saif_put_mclk(unsigned int saif_id)
> {
> - struct mxs_saif *saif = mxs_saif[saif_id];
> - u32 stat;
> + struct clk *clk;
>
> - if (!saif)
> - return -EINVAL;
> + clk = clk_get(NULL, "mxs_saif_mclk");
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
>
> - stat = __raw_readl(saif->base + SAIF_STAT);
> - if (stat & BM_SAIF_STAT_BUSY) {
> - dev_err(saif->dev, "error: busy\n");
> - return -EBUSY;
> - }
> + clk_disable_unprepare(clk);
> + clk_put(clk);
>
> - clk_disable_unprepare(saif->clk);
> -
> - /* disable MCLK output */
> - __raw_writel(BM_SAIF_CTRL_CLKGATE,
> - saif->base + SAIF_CTRL + MXS_SET_ADDR);
> - __raw_writel(BM_SAIF_CTRL_RUN,
> - saif->base + SAIF_CTRL + MXS_CLR_ADDR);
> -
> - saif->mclk_in_use = 0;
> return 0;
> }
> EXPORT_SYMBOL_GPL(mxs_saif_put_mclk);
> @@ -239,47 +227,33 @@ int mxs_saif_get_mclk(unsigned int saif_id,
> unsigned int mclk,
> unsigned int rate)
> {
> struct mxs_saif *saif = mxs_saif[saif_id];
> - u32 stat;
> int ret;
> struct mxs_saif *master_saif;
> + struct clk *clk;
>
> if (!saif)
> return -EINVAL;
>
> - /* Clear Reset */
> - __raw_writel(BM_SAIF_CTRL_SFTRST,
> - saif->base + SAIF_CTRL + MXS_CLR_ADDR);
> -
> - /* FIXME: need clear clk gate for register r/w */
> - __raw_writel(BM_SAIF_CTRL_CLKGATE,
> - saif->base + SAIF_CTRL + MXS_CLR_ADDR);
> -
> master_saif = mxs_saif_get_master(saif);
> if (saif != master_saif) {
> dev_err(saif->dev, "can not get mclk from a non-
> master saif\n");
> return -EINVAL;
> }
>
> - stat = __raw_readl(saif->base + SAIF_STAT);
> - if (stat & BM_SAIF_STAT_BUSY) {
> - dev_err(saif->dev, "error: busy\n");
> - return -EBUSY;
> - }
> + clk = clk_get(NULL, "mxs_saif_mclk");
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> +
> + ret = clk_prepare_enable(clk);
> + if (ret)
> + goto out;
>
> - saif->mclk_in_use = 1;
> ret = mxs_saif_set_clk(saif, mclk, rate);
> - if (ret)
> - return ret;
>
> - ret = clk_prepare_enable(saif->clk);
> - if (ret)
> - return ret;
> +out:
> + clk_put(clk);
>
> - /* enable MCLK output */
> - __raw_writel(BM_SAIF_CTRL_RUN,
> - saif->base + SAIF_CTRL + MXS_SET_ADDR);
> -
> - return 0;
> + return ret;
> }
> EXPORT_SYMBOL_GPL(mxs_saif_get_mclk);
>
> @@ -687,18 +661,92 @@ static irqreturn_t mxs_saif_irq(int irq, void
> *dev_id)
> return IRQ_HANDLED;
> }
>
> +#define to_mxs_saif(c) container_of(c, struct mxs_saif, div_clk.hw)
> +
> +static int mxs_saif_mclk_enable(struct clk_hw *hw)
> +{
> + struct mxs_saif *saif = to_mxs_saif(hw);
> +
> + /* Clear Reset */
> + __raw_writel(BM_SAIF_CTRL_SFTRST,
> + saif->base + SAIF_CTRL + MXS_CLR_ADDR);
> +
> + /* Clear clk gate */
> + __raw_writel(BM_SAIF_CTRL_CLKGATE,
> + saif->base + SAIF_CTRL + MXS_CLR_ADDR);
> +
> + /* enable MCLK output */
> + __raw_writel(BM_SAIF_CTRL_RUN,
> + saif->base + SAIF_CTRL + MXS_SET_ADDR);
> +
> + saif->mclk_in_use = 1;
> +
> + return 0;
> +}
> +
> +static void mxs_saif_mclk_disable(struct clk_hw *hw)
> +{
> + struct mxs_saif *saif = to_mxs_saif(hw);
> +
> + if (!saif->ongoing)
> + __raw_writel(BM_SAIF_CTRL_RUN,
> + saif->base + SAIF_CTRL + MXS_CLR_ADDR);
> +
> + saif->mclk_in_use = 0;
> +}
> +
> +static unsigned long mxs_saif_mclk_recalc_rate(struct clk_hw *hw,
> + unsigned long
> parent_rate)
> +{
> + return clk_divider_ops.recalc_rate(hw, parent_rate);
> +}
> +
> +static long mxs_saif_mclk_round_rate(struct clk_hw *hw, unsigned
> long rate,
> + unsigned long *parent_rate)
> +{
> + return clk_divider_ops.round_rate(hw, rate, parent_rate);
> +}
> +
> +static int mxs_saif_mclk_set_rate(struct clk_hw *hw, unsigned long
> rate,
> + unsigned long parent_rate)
> +{
> + return clk_divider_ops.set_rate(hw, rate, parent_rate);
> +}
> +
> +static const struct clk_ops mxs_saif_mclk_ops = {
> + .enable = mxs_saif_mclk_enable,
> + .disable = mxs_saif_mclk_disable,
> + .recalc_rate = mxs_saif_mclk_recalc_rate,
> + .round_rate = mxs_saif_mclk_round_rate,
> + .set_rate = mxs_saif_mclk_set_rate,
> +};
> +
> static int mxs_saif_mclk_init(struct platform_device *pdev)
> {
> struct mxs_saif *saif = platform_get_drvdata(pdev);
> struct device_node *np = pdev->dev.of_node;
> + struct clk_init_data init;
> + struct clk_divider *div;
> struct clk *clk;
> + const char *parent_name;
> int ret;
>
> - clk = clk_register_divider(&pdev->dev, "mxs_saif_mclk",
> - __clk_get_name(saif->clk), 0,
> - saif->base + SAIF_CTRL,
> - BP_SAIF_CTRL_BITCLK_MULT_RATE, 3,
> - 0, NULL);
> + parent_name = __clk_get_name(saif->clk);
> +
> + init.name = "mxs_saif_mclk";
> + init.ops = &mxs_saif_mclk_ops;
> + init.flags = CLK_GET_RATE_NOCACHE | CLK_IS_BASIC;
> + init.parent_names = &parent_name;
> + init.num_parents = 1;
> +
> + div = &saif->div_clk;
> + div->reg = saif->base + SAIF_CTRL;
> + div->shift = BP_SAIF_CTRL_BITCLK_MULT_RATE;
> + div->width = 3;
> + div->flags = CLK_DIVIDER_POWER_OF_TWO;
> + div->hw.init = &init;
> +
> + clk = clk_register(&pdev->dev, &div->hw);
> if (IS_ERR(clk)) {
> ret = PTR_ERR(clk);
> if (ret == -EEXIST)
> diff --git a/sound/soc/mxs/mxs-saif.h b/sound/soc/mxs/mxs-saif.h
> index 9a4c0b291b9e..e1bb5cb00ec0 100644
> --- a/sound/soc/mxs/mxs-saif.h
> +++ b/sound/soc/mxs/mxs-saif.h
> @@ -108,6 +108,7 @@
>
> #define MXS_SAIF_MCLK 0
>
> +#include <linux/clk-provider.h>
> #include "mxs-pcm.h"
>
> struct mxs_saif {
> @@ -128,6 +129,8 @@ struct mxs_saif {
> MXS_SAIF_STATE_STOPPED,
> MXS_SAIF_STATE_RUNNING,
> } state;
> +
> + struct clk_divider div_clk;
> };
>
> extern int mxs_saif_put_mclk(unsigned int saif_id);
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