2022-09-23 01:37:24

by chenweilong

Subject: [PATCH next v2] i2c: hisi: Add support to get clock frequency from clock property

Support the driver to obtain clock information by clk_rate or
clock property. Find clock first, if not, fall back to clk_rate.

Signed-off-by: Weilong Chen <[email protected]>
---
Change since v1:
- Ordered struct field to inverted triangle.
- Use devm_clk_get_optional_enabled().
- Use IS_ERR_OR_NULL.
Link: https://lore.kernel.org/lkml/[email protected]/

drivers/i2c/busses/i2c-hisi.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-hisi.c b/drivers/i2c/busses/i2c-hisi.c
index 67031024217c..b3bcce71dd2c 100644
--- a/drivers/i2c/busses/i2c-hisi.c
+++ b/drivers/i2c/busses/i2c-hisi.c
@@ -8,6 +8,7 @@
#include <linux/acpi.h>
#include <linux/bits.h>
#include <linux/bitfield.h>
+#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
@@ -90,6 +91,7 @@ struct hisi_i2c_controller {
struct i2c_adapter adapter;
void __iomem *iobase;
struct device *dev;
+ struct clk *clk;
int irq;

/* Intermediates for recording the transfer process */
@@ -456,10 +458,16 @@ static int hisi_i2c_probe(struct platform_device *pdev)
return ret;
}

- ret = device_property_read_u64(dev, "clk_rate", &clk_rate_hz);
- if (ret) {
- dev_err(dev, "failed to get clock frequency, ret = %d\n", ret);
- return ret;
+ ctlr->clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
+ if (IS_ERR_OR_NULL(ctlr->clk)) {
+ ret = device_property_read_u64(dev, "clk_rate", &clk_rate_hz);
+ if (ret) {
+ dev_err(dev, "failed to get clock frequency, ret = %d\n", ret);
+ return ret;
+ }
+ } else {
+
+ clk_rate_hz = clk_get_rate(ctlr->clk);
}

ctlr->clk_rate_khz = DIV_ROUND_UP_ULL(clk_rate_hz, HZ_PER_KHZ);
--
2.31.GIT

2022-09-26 09:15:50

by Yicong Yang

Subject: Re: [PATCH next v2] i2c: hisi: Add support to get clock frequency from clock property

On 2022/9/23 9:14, Weilong Chen wrote:
> Support the driver to obtain clock information by clk_rate or
> clock property. Find clock first, if not, fall back to clk_rate.
>
> Signed-off-by: Weilong Chen <[email protected]>
> ---
> Change since v1:
> - Ordered struct field to inverted triangle.
> - Use devm_clk_get_optional_enabled().
> - Use IS_ERR_OR_NULL.
> Link: https://lore.kernel.org/lkml/[email protected]/
>
> drivers/i2c/busses/i2c-hisi.c | 16 ++++++++++++----
> 1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-hisi.c b/drivers/i2c/busses/i2c-hisi.c
> index 67031024217c..b3bcce71dd2c 100644
> --- a/drivers/i2c/busses/i2c-hisi.c
> +++ b/drivers/i2c/busses/i2c-hisi.c
> @@ -8,6 +8,7 @@
> #include <linux/acpi.h>
> #include <linux/bits.h>
> #include <linux/bitfield.h>
> +#include <linux/clk.h>
> #include <linux/completion.h>
> #include <linux/i2c.h>
> #include <linux/interrupt.h>
> @@ -90,6 +91,7 @@ struct hisi_i2c_controller {
> struct i2c_adapter adapter;
> void __iomem *iobase;
> struct device *dev;
> + struct clk *clk;
> int irq;
>
> /* Intermediates for recording the transfer process */
> @@ -456,10 +458,16 @@ static int hisi_i2c_probe(struct platform_device *pdev)
> return ret;
> }
>
> - ret = device_property_read_u64(dev, "clk_rate", &clk_rate_hz);
> - if (ret) {
> - dev_err(dev, "failed to get clock frequency, ret = %d\n", ret);
> - return ret;
> + ctlr->clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
> + if (IS_ERR_OR_NULL(ctlr->clk)) {
> + ret = device_property_read_u64(dev, "clk_rate", &clk_rate_hz);
> + if (ret) {
> + dev_err(dev, "failed to get clock frequency, ret = %d\n", ret);
> + return ret;
> + }
> + } else {
> +

redundant blank line? with this addressed:

Acked-by: Yicong Yang <[email protected]>

> + clk_rate_hz = clk_get_rate(ctlr->clk);
> }
>
> ctlr->clk_rate_khz = DIV_ROUND_UP_ULL(clk_rate_hz, HZ_PER_KHZ);
>