[PATCH v12 03/12] dmaengine: qcom: bam_dma: Extend the driver's device match data

Bartosz Golaszewski
2026-03-10T15:44:52Z

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

In preparation for supporting the pipe locking feature flag, extend the
amount of information we can carry in device match data: create a
separate structure and make the register information one of its fields.
This way, in subsequent patches, it will be just a matter of adding a
new field to the device data.

Reviewed-by: Dmitry Baryshkov <lumag@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
drivers/dma/qcom/bam_dma.c | 28 ++++++++++++++++++++++------
1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index c8601bac555edf1bb4384fd39cb3449ec6e86334..8f6d03f6c673b57ed13aeca6c8331c71596d077b 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -113,6 +113,10 @@ struct reg_offset_data {
unsigned int pipe_mult, evnt_mult, ee_mult;
};

+struct bam_device_data {
+ const struct reg_offset_data *reg_info;
+};
+
static const struct reg_offset_data bam_v1_3_reg_info[] = {
[BAM_CTRL] = { 0x0F80, 0x00, 0x00, 0x00 },
[BAM_REVISION] = { 0x0F84, 0x00, 0x00, 0x00 },
@@ -142,6 +146,10 @@ static const struct reg_offset_data bam_v1_3_reg_info[] = {
[BAM_P_FIFO_SIZES] = { 0x1020, 0x00, 0x40, 0x00 },
};

+static const struct bam_device_data bam_v1_3_data = {
+ .reg_info = bam_v1_3_reg_info,
+};
+
static const struct reg_offset_data bam_v1_4_reg_info[] = {
[BAM_CTRL] = { 0x0000, 0x00, 0x00, 0x00 },
[BAM_REVISION] = { 0x0004, 0x00, 0x00, 0x00 },
@@ -171,6 +179,10 @@ static const struct reg_offset_data bam_v1_4_reg_info[] = {
[BAM_P_FIFO_SIZES] = { 0x1820, 0x00, 0x1000, 0x00 },
};

+static const struct bam_device_data bam_v1_4_data = {
+ .reg_info = bam_v1_4_reg_info,
+};
+
static const struct reg_offset_data bam_v1_7_reg_info[] = {
[BAM_CTRL] = { 0x00000, 0x00, 0x00, 0x00 },
[BAM_REVISION] = { 0x01000, 0x00, 0x00, 0x00 },
@@ -200,6 +212,10 @@ static const struct reg_offset_data bam_v1_7_reg_info[] = {
[BAM_P_FIFO_SIZES] = { 0x13820, 0x00, 0x1000, 0x00 },
};

+static const struct bam_device_data bam_v1_7_data = {
+ .reg_info = bam_v1_7_reg_info,
+};
+
/* BAM CTRL */
#define BAM_SW_RST BIT(0)
#define BAM_EN BIT(1)
@@ -393,7 +409,7 @@ struct bam_device {
bool powered_remotely;
u32 active_channels;

- const struct reg_offset_data *layout;
+ const struct bam_device_data *dev_data;

struct clk *bamclk;
int irq;
@@ -411,7 +427,7 @@ struct bam_device {
static inline void __iomem *bam_addr(struct bam_device *bdev, u32 pipe,
enum bam_reg reg)
{
- const struct reg_offset_data r = bdev->layout[reg];
+ const struct reg_offset_data r = bdev->dev_data->reg_info[reg];

return bdev->regs + r.base_offset +
r.pipe_mult * pipe +
@@ -1205,9 +1221,9 @@ static void bam_channel_init(struct bam_device *bdev, struct bam_chan *bchan,
}

static const struct of_device_id bam_of_match[] = {
- { .compatible = "qcom,bam-v1.3.0", .data = &bam_v1_3_reg_info },
- { .compatible = "qcom,bam-v1.4.0", .data = &bam_v1_4_reg_info },
- { .compatible = "qcom,bam-v1.7.0", .data = &bam_v1_7_reg_info },
+ { .compatible = "qcom,bam-v1.3.0", .data = &bam_v1_3_data },
+ { .compatible = "qcom,bam-v1.4.0", .data = &bam_v1_4_data },
+ { .compatible = "qcom,bam-v1.7.0", .data = &bam_v1_7_data },
{}
};

@@ -1231,7 +1247,7 @@ static int bam_dma_probe(struct platform_device *pdev)
return -ENODEV;
}

- bdev->layout = match->data;
+ bdev->dev_data = match->data;

bdev->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(bdev->regs))

--
2.47.3