2014-07-11 12:04:26

by Tushar Behera

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Subject: [PATCH V2 0/3] clk: exynos-audss: Adapt to exising clock framework

Generic cleanup and usage of samsung clock register/unregister APIs.

The patches are tested on Exynos5800 based Peach-Pi board. More tests are
welcome.

Tushar Behera (3):
clk: exynos-audss: Simplify code to get clock names
clk: samsung: Add API to unregister clocks
clk: exynos-audss: Use samsung clock APIs to register/unregister
clocks

drivers/clk/samsung/clk-exynos-audss.c | 179 +++++++++++++-------------------
drivers/clk/samsung/clk.c | 19 ++++
drivers/clk/samsung/clk.h | 2 +
3 files changed, 95 insertions(+), 105 deletions(-)

--
1.7.9.5


2014-07-11 12:04:29

by Tushar Behera

[permalink] [raw]
Subject: [PATCH V2 1/3] clk: exynos-audss: Simplify code to get clock names

Instead of getting the clock names individually, it would be good to put
the logic within a loop.

Signed-off-by: Tushar Behera <[email protected]>
---
Changes for V2:
* Calling clk_put as soon as the clock is not required anymore

drivers/clk/samsung/clk-exynos-audss.c | 35 +++++++++++++++++---------------
1 file changed, 19 insertions(+), 16 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos-audss.c b/drivers/clk/samsung/clk-exynos-audss.c
index 13eae14c..1a5294c 100644
--- a/drivers/clk/samsung/clk-exynos-audss.c
+++ b/drivers/clk/samsung/clk-exynos-audss.c
@@ -80,10 +80,14 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
{
int i, ret = 0;
struct resource *res;
+ struct clk *tmp;
+ const char *clk_name_ref[] = {
+ "pll_ref", "pll_in", "cdclk", "sclk_audio", "sclk_pcm_in" };
+ const char *clk_name_actual[] = {
+ "fin_pll", "fout_epll", "cdclk0", "sclk_audio0", "sclk_pcm0"};
const char *mout_audss_p[] = {"fin_pll", "fout_epll"};
const char *mout_i2s_p[] = {"mout_audss", "cdclk0", "sclk_audio0"};
const char *sclk_pcm_p = "sclk_pcm0";
- struct clk *pll_ref, *pll_in, *cdclk, *sclk_audio, *sclk_pcm_in;
const struct of_device_id *match;
enum exynos_audss_clk_type variant;

@@ -111,23 +115,25 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
else
clk_data.clk_num = EXYNOS_AUDSS_MAX_CLKS - 1;

- pll_ref = devm_clk_get(&pdev->dev, "pll_ref");
- pll_in = devm_clk_get(&pdev->dev, "pll_in");
- if (!IS_ERR(pll_ref))
- mout_audss_p[0] = __clk_get_name(pll_ref);
- if (!IS_ERR(pll_in))
- mout_audss_p[1] = __clk_get_name(pll_in);
+ for (i = 0; i < ARRAY_SIZE(clk_name_ref); i++) {
+ tmp = clk_get(&pdev->dev, clk_name_ref[i]);
+ if (!IS_ERR(tmp)) {
+ clk_name_actual[i] = __clk_get_name(tmp);
+ clk_put(tmp);
+ }
+ }
+
+ mout_audss_p[0] = clk_name_actual[0];
+ mout_audss_p[1] = clk_name_actual[1];
+ mout_i2s_p[1] = clk_name_actual[2];
+ mout_i2s_p[2] = clk_name_actual[3];
+ sclk_pcm_p = clk_name_actual[4];
+
clk_table[EXYNOS_MOUT_AUDSS] = clk_register_mux(NULL, "mout_audss",
mout_audss_p, ARRAY_SIZE(mout_audss_p),
CLK_SET_RATE_NO_REPARENT,
reg_base + ASS_CLK_SRC, 0, 1, 0, &lock);

- cdclk = devm_clk_get(&pdev->dev, "cdclk");
- sclk_audio = devm_clk_get(&pdev->dev, "sclk_audio");
- if (!IS_ERR(cdclk))
- mout_i2s_p[1] = __clk_get_name(cdclk);
- if (!IS_ERR(sclk_audio))
- mout_i2s_p[2] = __clk_get_name(sclk_audio);
clk_table[EXYNOS_MOUT_I2S] = clk_register_mux(NULL, "mout_i2s",
mout_i2s_p, ARRAY_SIZE(mout_i2s_p),
CLK_SET_RATE_NO_REPARENT,
@@ -161,9 +167,6 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
"sclk_pcm", CLK_SET_RATE_PARENT,
reg_base + ASS_CLK_GATE, 4, 0, &lock);

- sclk_pcm_in = devm_clk_get(&pdev->dev, "sclk_pcm_in");
- if (!IS_ERR(sclk_pcm_in))
- sclk_pcm_p = __clk_get_name(sclk_pcm_in);
clk_table[EXYNOS_SCLK_PCM] = clk_register_gate(NULL, "sclk_pcm",
sclk_pcm_p, CLK_SET_RATE_PARENT,
reg_base + ASS_CLK_GATE, 5, 0, &lock);
--
1.7.9.5

2014-07-11 12:04:33

by Tushar Behera

[permalink] [raw]
Subject: [PATCH V2 2/3] clk: samsung: Add API to unregister clocks

Added an API to unregister all the clocks defined within a context. This
is helpful in case where the clock is registered through a platform
driver and we want to unregister the clocks during remove callback.

Signed-off-by: Tushar Behera <[email protected]>
---
Changelog:
This is new patch required because of changes to patch 3/3.

drivers/clk/samsung/clk.c | 19 +++++++++++++++++++
drivers/clk/samsung/clk.h | 2 ++
2 files changed, 21 insertions(+)

diff --git a/drivers/clk/samsung/clk.c b/drivers/clk/samsung/clk.c
index 49629c7..b9310b9 100644
--- a/drivers/clk/samsung/clk.c
+++ b/drivers/clk/samsung/clk.c
@@ -83,6 +83,25 @@ struct samsung_clk_provider *__init samsung_clk_init(struct device_node *np,
return ctx;
}

+/* API to remove a clock provider */
+void samsung_clk_exit(struct device_node *np, struct samsung_clk_provider *ctx)
+{
+ int i;
+
+ if (np)
+ of_clk_del_provider(np);
+
+ if (!ctx)
+ return;
+
+ for (i = 0; i < ctx->clk_data.clk_num; i++)
+ if (!IS_ERR(ctx->clk_data.clks[i]))
+ clk_unregister(ctx->clk_data.clks[i]);
+
+ kfree(ctx->clk_data.clks);
+ kfree(ctx);
+}
+
/* add a clock instance to the clock lookup table used for dt based lookup */
void samsung_clk_add_lookup(struct samsung_clk_provider *ctx, struct clk *clk,
unsigned int id)
diff --git a/drivers/clk/samsung/clk.h b/drivers/clk/samsung/clk.h
index 9693b80..8ecc85a 100644
--- a/drivers/clk/samsung/clk.h
+++ b/drivers/clk/samsung/clk.h
@@ -327,6 +327,8 @@ struct samsung_pll_clock {
extern struct samsung_clk_provider *__init samsung_clk_init(
struct device_node *np, void __iomem *base,
unsigned long nr_clks);
+extern void samsung_clk_exit(struct device_node *np,
+ struct samsung_clk_provider *ctx);
extern void __init samsung_clk_of_register_fixed_ext(
struct samsung_clk_provider *ctx,
struct samsung_fixed_rate_clock *fixed_rate_clk,
--
1.7.9.5

2014-07-11 12:04:38

by Tushar Behera

[permalink] [raw]
Subject: [PATCH V2 3/3] clk: exynos-audss: Use samsung clock APIs to register/unregister clocks

Using samsung clock APIs to register/unregister clocks will save some
lines of code.

Signed-off-by: Tushar Behera <[email protected]>
---
Changes of v2:
* Retain platform driver structure.

drivers/clk/samsung/clk-exynos-audss.c | 146 ++++++++++++--------------------
1 file changed, 56 insertions(+), 90 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos-audss.c b/drivers/clk/samsung/clk-exynos-audss.c
index 1a5294c..2b90967 100644
--- a/drivers/clk/samsung/clk-exynos-audss.c
+++ b/drivers/clk/samsung/clk-exynos-audss.c
@@ -19,16 +19,16 @@

#include <dt-bindings/clock/exynos-audss-clk.h>

+#include "clk.h"
+
enum exynos_audss_clk_type {
TYPE_EXYNOS4210,
TYPE_EXYNOS5250,
TYPE_EXYNOS5420,
};

-static DEFINE_SPINLOCK(lock);
-static struct clk **clk_table;
+static struct samsung_clk_provider *ctx;
static void __iomem *reg_base;
-static struct clk_onecell_data clk_data;

#define ASS_CLK_SRC 0x0
#define ASS_CLK_DIV 0x4
@@ -78,7 +78,7 @@ static const struct of_device_id exynos_audss_clk_of_match[] = {
/* register exynos_audss clocks */
static int exynos_audss_clk_probe(struct platform_device *pdev)
{
- int i, ret = 0;
+ int i;
struct resource *res;
struct clk *tmp;
const char *clk_name_ref[] = {
@@ -87,14 +87,51 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
"fin_pll", "fout_epll", "cdclk0", "sclk_audio0", "sclk_pcm0"};
const char *mout_audss_p[] = {"fin_pll", "fout_epll"};
const char *mout_i2s_p[] = {"mout_audss", "cdclk0", "sclk_audio0"};
- const char *sclk_pcm_p = "sclk_pcm0";
+ char sclk_pcm_p[32];
const struct of_device_id *match;
enum exynos_audss_clk_type variant;

+ struct samsung_mux_clock exynos_audss_mux_clks[] = {
+ MUX(EXYNOS_MOUT_AUDSS, "mout_audss", mout_audss_p,
+ ASS_CLK_SRC, 0, 1),
+ MUX(EXYNOS_MOUT_I2S, "mout_i2s", mout_i2s_p,
+ ASS_CLK_SRC, 2, 2),
+ };
+
+ struct samsung_div_clock exynos_audss_div_clks[] = {
+ DIV(EXYNOS_DOUT_SRP, "dout_srp", "mout_audss",
+ ASS_CLK_DIV, 0, 4),
+ DIV(EXYNOS_DOUT_AUD_BUS, "dout_aud_bus", "dout_srp",
+ ASS_CLK_DIV, 4, 4),
+ DIV(EXYNOS_DOUT_I2S, "dout_i2s", "mout_i2s", ASS_CLK_DIV, 8, 4),
+ };
+
+ struct samsung_gate_clock exynos_audss_gate_clks[] = {
+ GATE(EXYNOS_SRP_CLK, "srp_clk", "dout_srp",
+ ASS_CLK_GATE, 0, CLK_SET_RATE_PARENT, 0),
+ GATE(EXYNOS_I2S_BUS, "i2s_bus", "dout_aud_bus",
+ ASS_CLK_GATE, 2, CLK_SET_RATE_PARENT, 0),
+ GATE(EXYNOS_SCLK_I2S, "sclk_i2s", "dout_i2s",
+ ASS_CLK_GATE, 3, CLK_SET_RATE_PARENT, 0),
+ GATE(EXYNOS_PCM_BUS, "pcm_bus", "sclk_pcm",
+ ASS_CLK_GATE, 4, CLK_SET_RATE_PARENT, 0),
+ GATE(EXYNOS_SCLK_PCM, "sclk_pcm", sclk_pcm_p,
+ ASS_CLK_GATE, 5, CLK_SET_RATE_PARENT, 0),
+ };
+
+ struct samsung_gate_clock exynos5420_audss_gate_clks[] = {
+ GATE(EXYNOS_ADMA, "adma", "dout_srp",
+ ASS_CLK_GATE, 9, CLK_SET_RATE_PARENT, 0),
+ };
+
+ int nr_clks = EXYNOS_AUDSS_MAX_CLKS;
+
match = of_match_node(exynos_audss_clk_of_match, pdev->dev.of_node);
if (!match)
return -EINVAL;
variant = (enum exynos_audss_clk_type)match->data;
+ if (variant != TYPE_EXYNOS5420)
+ nr_clks--;

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
reg_base = devm_ioremap_resource(&pdev->dev, res);
@@ -103,17 +140,11 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
return PTR_ERR(reg_base);
}

- clk_table = devm_kzalloc(&pdev->dev,
- sizeof(struct clk *) * EXYNOS_AUDSS_MAX_CLKS,
- GFP_KERNEL);
- if (!clk_table)
+ ctx = samsung_clk_init(pdev->dev.of_node, reg_base, nr_clks);
+ if (!ctx) {
+ dev_err(&pdev->dev, "failed to get clock provier context\n");
return -ENOMEM;
-
- clk_data.clks = clk_table;
- if (variant == TYPE_EXYNOS5420)
- clk_data.clk_num = EXYNOS_AUDSS_MAX_CLKS;
- else
- clk_data.clk_num = EXYNOS_AUDSS_MAX_CLKS - 1;
+ }

for (i = 0; i < ARRAY_SIZE(clk_name_ref); i++) {
tmp = clk_get(&pdev->dev, clk_name_ref[i]);
@@ -127,69 +158,20 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
mout_audss_p[1] = clk_name_actual[1];
mout_i2s_p[1] = clk_name_actual[2];
mout_i2s_p[2] = clk_name_actual[3];
- sclk_pcm_p = clk_name_actual[4];
-
- clk_table[EXYNOS_MOUT_AUDSS] = clk_register_mux(NULL, "mout_audss",
- mout_audss_p, ARRAY_SIZE(mout_audss_p),
- CLK_SET_RATE_NO_REPARENT,
- reg_base + ASS_CLK_SRC, 0, 1, 0, &lock);
-
- clk_table[EXYNOS_MOUT_I2S] = clk_register_mux(NULL, "mout_i2s",
- mout_i2s_p, ARRAY_SIZE(mout_i2s_p),
- CLK_SET_RATE_NO_REPARENT,
- reg_base + ASS_CLK_SRC, 2, 2, 0, &lock);
+ strncpy(sclk_pcm_p, clk_name_actual[4], strlen(clk_name_actual[4]));

- clk_table[EXYNOS_DOUT_SRP] = clk_register_divider(NULL, "dout_srp",
- "mout_audss", 0, reg_base + ASS_CLK_DIV, 0, 4,
- 0, &lock);
+ samsung_clk_register_mux(ctx, exynos_audss_mux_clks,
+ ARRAY_SIZE(exynos_audss_mux_clks));

- clk_table[EXYNOS_DOUT_AUD_BUS] = clk_register_divider(NULL,
- "dout_aud_bus", "dout_srp", 0,
- reg_base + ASS_CLK_DIV, 4, 4, 0, &lock);
+ samsung_clk_register_div(ctx, exynos_audss_div_clks,
+ ARRAY_SIZE(exynos_audss_div_clks));

- clk_table[EXYNOS_DOUT_I2S] = clk_register_divider(NULL, "dout_i2s",
- "mout_i2s", 0, reg_base + ASS_CLK_DIV, 8, 4, 0,
- &lock);
-
- clk_table[EXYNOS_SRP_CLK] = clk_register_gate(NULL, "srp_clk",
- "dout_srp", CLK_SET_RATE_PARENT,
- reg_base + ASS_CLK_GATE, 0, 0, &lock);
-
- clk_table[EXYNOS_I2S_BUS] = clk_register_gate(NULL, "i2s_bus",
- "dout_aud_bus", CLK_SET_RATE_PARENT,
- reg_base + ASS_CLK_GATE, 2, 0, &lock);
-
- clk_table[EXYNOS_SCLK_I2S] = clk_register_gate(NULL, "sclk_i2s",
- "dout_i2s", CLK_SET_RATE_PARENT,
- reg_base + ASS_CLK_GATE, 3, 0, &lock);
-
- clk_table[EXYNOS_PCM_BUS] = clk_register_gate(NULL, "pcm_bus",
- "sclk_pcm", CLK_SET_RATE_PARENT,
- reg_base + ASS_CLK_GATE, 4, 0, &lock);
-
- clk_table[EXYNOS_SCLK_PCM] = clk_register_gate(NULL, "sclk_pcm",
- sclk_pcm_p, CLK_SET_RATE_PARENT,
- reg_base + ASS_CLK_GATE, 5, 0, &lock);
+ samsung_clk_register_gate(ctx, exynos_audss_gate_clks,
+ ARRAY_SIZE(exynos_audss_gate_clks));

if (variant == TYPE_EXYNOS5420) {
- clk_table[EXYNOS_ADMA] = clk_register_gate(NULL, "adma",
- "dout_srp", CLK_SET_RATE_PARENT,
- reg_base + ASS_CLK_GATE, 9, 0, &lock);
- }
-
- for (i = 0; i < clk_data.clk_num; i++) {
- if (IS_ERR(clk_table[i])) {
- dev_err(&pdev->dev, "failed to register clock %d\n", i);
- ret = PTR_ERR(clk_table[i]);
- goto unregister;
- }
- }
-
- ret = of_clk_add_provider(pdev->dev.of_node, of_clk_src_onecell_get,
- &clk_data);
- if (ret) {
- dev_err(&pdev->dev, "failed to add clock provider\n");
- goto unregister;
+ samsung_clk_register_gate(ctx, exynos5420_audss_gate_clks,
+ ARRAY_SIZE(exynos5420_audss_gate_clks));
}

#ifdef CONFIG_PM_SLEEP
@@ -199,27 +181,11 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "setup completed\n");

return 0;
-
-unregister:
- for (i = 0; i < clk_data.clk_num; i++) {
- if (!IS_ERR(clk_table[i]))
- clk_unregister(clk_table[i]);
- }
-
- return ret;
}

static int exynos_audss_clk_remove(struct platform_device *pdev)
{
- int i;
-
- of_clk_del_provider(pdev->dev.of_node);
-
- for (i = 0; i < clk_data.clk_num; i++) {
- if (!IS_ERR(clk_table[i]))
- clk_unregister(clk_table[i]);
- }
-
+ samsung_clk_exit(pdev->dev.of_node, ctx);
return 0;
}

--
1.7.9.5

2014-07-14 15:34:54

by Sylwester Nawrocki

[permalink] [raw]
Subject: Re: [PATCH V2 3/3] clk: exynos-audss: Use samsung clock APIs to register/unregister clocks

On 11/07/14 14:00, Tushar Behera wrote:
> @@ -103,17 +140,11 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
> return PTR_ERR(reg_base);
> }
>
> - clk_table = devm_kzalloc(&pdev->dev,
> - sizeof(struct clk *) * EXYNOS_AUDSS_MAX_CLKS,
> - GFP_KERNEL);
> - if (!clk_table)
> + ctx = samsung_clk_init(pdev->dev.of_node, reg_base, nr_clks);

There is an issue here that this registers the clk provider before all
its clocks are registered with the clk core. Therefore it introduces
a race condition.

Please have a look at patch [1], you may want to rebase this series
onto that patch.

> + samsung_clk_register_div(ctx, exynos_audss_div_clks,
> + ARRAY_SIZE(exynos_audss_div_clks));
[...]
> + samsung_clk_register_gate(ctx, exynos_audss_gate_clks,
> + ARRAY_SIZE(exynos_audss_gate_clks));
[...]
> - ret = of_clk_add_provider(pdev->dev.of_node, of_clk_src_onecell_get,
> - &clk_data);
> - if (ret) {
> - dev_err(&pdev->dev, "failed to add clock provider\n");
> - goto unregister;
> + samsung_clk_register_gate(ctx, exynos5420_audss_gate_clks,
> + ARRAY_SIZE(exynos5420_audss_gate_clks));
> }

[1]
https://git.kernel.org/cgit/linux/kernel/git/tfiga/samsung-clk.git/commit/?h=samsung-clk-next&id=d5e136a21b2028fb1f45143ea7112d5869bfc6c7

--
Regards,
Sylwester

2014-07-15 03:03:01

by Tushar Behera

[permalink] [raw]
Subject: Re: [PATCH V2 3/3] clk: exynos-audss: Use samsung clock APIs to register/unregister clocks

On Mon, Jul 14, 2014 at 9:04 PM, Sylwester Nawrocki
<[email protected]> wrote:
> On 11/07/14 14:00, Tushar Behera wrote:
>> @@ -103,17 +140,11 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
>> return PTR_ERR(reg_base);
>> }
>>
>> - clk_table = devm_kzalloc(&pdev->dev,
>> - sizeof(struct clk *) * EXYNOS_AUDSS_MAX_CLKS,
>> - GFP_KERNEL);
>> - if (!clk_table)
>> + ctx = samsung_clk_init(pdev->dev.of_node, reg_base, nr_clks);
>
> There is an issue here that this registers the clk provider before all
> its clocks are registered with the clk core. Therefore it introduces
> a race condition.
>
> Please have a look at patch [1], you may want to rebase this series
> onto that patch.
>

Thanks for the pointer. I will re-post.

>> + samsung_clk_register_div(ctx, exynos_audss_div_clks,
>> + ARRAY_SIZE(exynos_audss_div_clks));
> [...]
>> + samsung_clk_register_gate(ctx, exynos_audss_gate_clks,
>> + ARRAY_SIZE(exynos_audss_gate_clks));
> [...]
>> - ret = of_clk_add_provider(pdev->dev.of_node, of_clk_src_onecell_get,
>> - &clk_data);
>> - if (ret) {
>> - dev_err(&pdev->dev, "failed to add clock provider\n");
>> - goto unregister;
>> + samsung_clk_register_gate(ctx, exynos5420_audss_gate_clks,
>> + ARRAY_SIZE(exynos5420_audss_gate_clks));
>> }
>
> [1]
> https://git.kernel.org/cgit/linux/kernel/git/tfiga/samsung-clk.git/commit/?h=samsung-clk-next&id=d5e136a21b2028fb1f45143ea7112d5869bfc6c7
>
> --
> Regards,
> Sylwester