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[PATCH v4 12/13] i2c: qcom-geni: Store of_device_id data in driver private struct

Praveen Talari posted 13 patches 1 week ago
There is a newer version of this series
[PATCH v4 12/13] i2c: qcom-geni: Store of_device_id data in driver private struct
Posted by Praveen Talari 1 week ago 
To avoid repeatedly fetching and checking platform data across various
functions, store the struct of_device_id data directly in the i2c
private structure. This change enhances code maintainability and reduces
redundancy.

Acked-by: Viken Dadhaniya <viken.dadhaniya@oss.qualcomm.com>
Signed-off-by: Praveen Talari <praveen.talari@oss.qualcomm.com>
---
v3->v4
- Added Acked-by tag.

Konrad
- Removed icc_ddr from platfrom data struct
---
 drivers/i2c/busses/i2c-qcom-geni.c | 30 ++++++++++++++----------------
 1 file changed, 14 insertions(+), 16 deletions(-)

diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
index 4ff84bb0fff5..8fd62d659c2a 100644
--- a/drivers/i2c/busses/i2c-qcom-geni.c
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -77,6 +77,12 @@ enum geni_i2c_err_code {
 #define XFER_TIMEOUT		HZ
 #define RST_TIMEOUT		HZ
 
+struct geni_i2c_desc {
+	bool has_core_clk;
+	bool no_dma_support;
+	unsigned int tx_fifo_depth;
+};
+
 #define QCOM_I2C_MIN_NUM_OF_MSGS_MULTI_DESC	2
 
 /**
@@ -122,13 +128,7 @@ struct geni_i2c_dev {
 	bool is_tx_multi_desc_xfer;
 	u32 num_msgs;
 	struct geni_i2c_gpi_multi_desc_xfer i2c_multi_desc_config;
-};
-
-struct geni_i2c_desc {
-	bool has_core_clk;
-	char *icc_ddr;
-	bool no_dma_support;
-	unsigned int tx_fifo_depth;
+	const struct geni_i2c_desc *dev_data;
 };
 
 struct geni_i2c_err_log {
@@ -979,7 +979,6 @@ static int setup_gpi_dma(struct geni_i2c_dev *gi2c)
 
 static int geni_i2c_init(struct geni_i2c_dev *gi2c)
 {
-	const struct geni_i2c_desc *desc = NULL;
 	u32 proto, tx_depth;
 	bool fifo_disable;
 	int ret;
@@ -1002,8 +1001,7 @@ static int geni_i2c_init(struct geni_i2c_dev *gi2c)
 		goto err;
 	}
 
-	desc = device_get_match_data(gi2c->se.dev);
-	if (desc && desc->no_dma_support) {
+	if (gi2c->dev_data->no_dma_support) {
 		fifo_disable = false;
 		gi2c->no_dma = true;
 	} else {
@@ -1023,8 +1021,8 @@ static int geni_i2c_init(struct geni_i2c_dev *gi2c)
 		tx_depth = geni_se_get_tx_fifo_depth(&gi2c->se);
 
 		/* I2C Master Hub Serial Elements doesn't have the HW_PARAM_0 register */
-		if (!tx_depth && desc)
-			tx_depth = desc->tx_fifo_depth;
+		if (!tx_depth && gi2c->dev_data->has_core_clk)
+			tx_depth = gi2c->dev_data->tx_fifo_depth;
 
 		if (!tx_depth) {
 			ret = dev_err_probe(gi2c->se.dev, -EINVAL,
@@ -1067,7 +1065,6 @@ static int geni_i2c_probe(struct platform_device *pdev)
 	struct geni_i2c_dev *gi2c;
 	int ret;
 	struct device *dev = &pdev->dev;
-	const struct geni_i2c_desc *desc = NULL;
 
 	gi2c = devm_kzalloc(dev, sizeof(*gi2c), GFP_KERNEL);
 	if (!gi2c)
@@ -1079,7 +1076,7 @@ static int geni_i2c_probe(struct platform_device *pdev)
 	if (IS_ERR(gi2c->se.base))
 		return PTR_ERR(gi2c->se.base);
 
-	desc = device_get_match_data(&pdev->dev);
+	gi2c->dev_data = device_get_match_data(&pdev->dev);
 
 	ret = device_property_read_u32(dev, "clock-frequency",
 				       &gi2c->clk_freq_out);
@@ -1218,15 +1215,16 @@ static const struct dev_pm_ops geni_i2c_pm_ops = {
 									NULL)
 };
 
+static const struct geni_i2c_desc geni_i2c = {};
+
 static const struct geni_i2c_desc i2c_master_hub = {
 	.has_core_clk = true,
-	.icc_ddr = NULL,
 	.no_dma_support = true,
 	.tx_fifo_depth = 16,
 };
 
 static const struct of_device_id geni_i2c_dt_match[] = {
-	{ .compatible = "qcom,geni-i2c" },
+	{ .compatible = "qcom,geni-i2c", .data = &geni_i2c },
 	{ .compatible = "qcom,geni-i2c-master-hub", .data = &i2c_master_hub },
 	{}
 };
-- 
2.34.1
Re: [PATCH v4 12/13] i2c: qcom-geni: Store of_device_id data in driver private struct
Posted by Konrad Dybcio 6 days, 7 hours ago 
On 2/2/26 7:09 PM, Praveen Talari wrote:
> To avoid repeatedly fetching and checking platform data across various
> functions, store the struct of_device_id data directly in the i2c
> private structure. This change enhances code maintainability and reduces
> redundancy.
> 
> Acked-by: Viken Dadhaniya <viken.dadhaniya@oss.qualcomm.com>
> Signed-off-by: Praveen Talari <praveen.talari@oss.qualcomm.com>
> ---

[...]

>  
> -	desc = device_get_match_data(&pdev->dev);
> +	gi2c->dev_data = device_get_match_data(&pdev->dev);

Because you dereference it unconditionally later, this should be
null-checked

Konrad
Re: [PATCH v4 12/13] i2c: qcom-geni: Store of_device_id data in driver private struct
Posted by Praveen Talari 5 days, 15 hours ago 
Hi Konrad,

On 2/3/2026 5:55 PM, Konrad Dybcio wrote:
> On 2/2/26 7:09 PM, Praveen Talari wrote:
>> To avoid repeatedly fetching and checking platform data across various
>> functions, store the struct of_device_id data directly in the i2c
>> private structure. This change enhances code maintainability and reduces
>> redundancy.
>>
>> Acked-by: Viken Dadhaniya <viken.dadhaniya@oss.qualcomm.com>
>> Signed-off-by: Praveen Talari <praveen.talari@oss.qualcomm.com>
>> ---
> 
> [...]
> 
>>   
>> -	desc = device_get_match_data(&pdev->dev);
>> +	gi2c->dev_data = device_get_match_data(&pdev->dev);
> 
> Because you dereference it unconditionally later, this should be
> null-checked

Initially this was added, but based on Bjorn’s comment like there is no 
possibility of getting a null value here since we are already adding the 
platform data to compatibles

Thanks,
Praveen Talari

> 
> Konrad
Re: [PATCH v4 12/13] i2c: qcom-geni: Store of_device_id data in driver private struct
Posted by Konrad Dybcio 5 days, 6 hours ago 
On 2/4/26 6:04 AM, Praveen Talari wrote:
> Hi Konrad,
> 
> On 2/3/2026 5:55 PM, Konrad Dybcio wrote:
>> On 2/2/26 7:09 PM, Praveen Talari wrote:
>>> To avoid repeatedly fetching and checking platform data across various
>>> functions, store the struct of_device_id data directly in the i2c
>>> private structure. This change enhances code maintainability and reduces
>>> redundancy.
>>>
>>> Acked-by: Viken Dadhaniya <viken.dadhaniya@oss.qualcomm.com>
>>> Signed-off-by: Praveen Talari <praveen.talari@oss.qualcomm.com>
>>> ---
>>
>> [...]
>>
>>>   -    desc = device_get_match_data(&pdev->dev);
>>> +    gi2c->dev_data = device_get_match_data(&pdev->dev);
>>
>> Because you dereference it unconditionally later, this should be
>> null-checked
> 
> Initially this was added, but based on Bjorn’s comment like there is no possibility of getting a null value here since we are already adding the platform data to compatibles

The ACPI match entries don't have it, which I think gives a good
example of how easy this may be overlooked

Konrad
Re: [PATCH v4 12/13] i2c: qcom-geni: Store of_device_id data in driver private struct
Posted by Praveen Talari 5 days, 3 hours ago 
Hi Konrad,

On 2/4/2026 7:17 PM, Konrad Dybcio wrote:
> On 2/4/26 6:04 AM, Praveen Talari wrote:
>> Hi Konrad,
>>
>> On 2/3/2026 5:55 PM, Konrad Dybcio wrote:
>>> On 2/2/26 7:09 PM, Praveen Talari wrote:
>>>> To avoid repeatedly fetching and checking platform data across various
>>>> functions, store the struct of_device_id data directly in the i2c
>>>> private structure. This change enhances code maintainability and reduces
>>>> redundancy.
>>>>
>>>> Acked-by: Viken Dadhaniya <viken.dadhaniya@oss.qualcomm.com>
>>>> Signed-off-by: Praveen Talari <praveen.talari@oss.qualcomm.com>
>>>> ---
>>>
>>> [...]
>>>
>>>>    -    desc = device_get_match_data(&pdev->dev);
>>>> +    gi2c->dev_data = device_get_match_data(&pdev->dev);
>>>
>>> Because you dereference it unconditionally later, this should be
>>> null-checked
>>
>> Initially this was added, but based on Bjorn’s comment like there is no possibility of getting a null value here since we are already adding the platform data to compatibles
> 
> The ACPI match entries don't have it, which I think gives a good
> example of how easy this may be overlooked
Sure, will update in next patch.

Thanks,
Praveen Talari
> 
> Konrad

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