[PATCH 1/8] reset: amlogic: convert driver to regmap

Jerome Brunet
2024-07-10T16:25:39Z

To allow using the same driver for the main reset controller and the
auxiliary ones embedded in the clock controllers, convert the
the Amlogic reset driver to regmap.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
drivers/reset/reset-meson.c | 80 ++++++++++++++++++++-----------------
1 file changed, 44 insertions(+), 36 deletions(-)

diff --git a/drivers/reset/reset-meson.c b/drivers/reset/reset-meson.c
index f78be97898bc..8f3d6e9df235 100644
--- a/drivers/reset/reset-meson.c
+++ b/drivers/reset/reset-meson.c
@@ -11,36 +11,44 @@
#include <linux/of.h>
#include <linux/module.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>
#include <linux/reset-controller.h>
#include <linux/slab.h>
#include <linux/types.h>

-#define BITS_PER_REG 32
-
struct meson_reset_param {
int reg_count;
int level_offset;
};

struct meson_reset {
- void __iomem *reg_base;
const struct meson_reset_param *param;
struct reset_controller_dev rcdev;
- spinlock_t lock;
+ struct regmap *map;
};

+static void meson_reset_offset_and_bit(struct meson_reset *data,
+ unsigned long id,
+ unsigned int *offset,
+ unsigned int *bit)
+{
+ unsigned int stride = regmap_get_reg_stride(data->map);
+
+ *offset = (id / (stride * BITS_PER_BYTE)) * stride;
+ *bit = id % (stride * BITS_PER_BYTE);
+}
+
static int meson_reset_reset(struct reset_controller_dev *rcdev,
- unsigned long id)
+ unsigned long id)
{
struct meson_reset *data =
container_of(rcdev, struct meson_reset, rcdev);
- unsigned int bank = id / BITS_PER_REG;
- unsigned int offset = id % BITS_PER_REG;
- void __iomem *reg_addr = data->reg_base + (bank << 2);
+ unsigned int offset, bit;

- writel(BIT(offset), reg_addr);
+ meson_reset_offset_and_bit(data, id, &offset, &bit);

- return 0;
+ return regmap_update_bits(data->map, offset,
+ BIT(bit), BIT(bit));
}

static int meson_reset_level(struct reset_controller_dev *rcdev,
@@ -48,25 +56,13 @@ static int meson_reset_level(struct reset_controller_dev *rcdev,
{
struct meson_reset *data =
container_of(rcdev, struct meson_reset, rcdev);
- unsigned int bank = id / BITS_PER_REG;
- unsigned int offset = id % BITS_PER_REG;
- void __iomem *reg_addr;
- unsigned long flags;
- u32 reg;
+ unsigned int offset, bit;

- reg_addr = data->reg_base + data->param->level_offset + (bank << 2);
+ meson_reset_offset_and_bit(data, id, &offset, &bit);
+ offset += data->param->level_offset;

- spin_lock_irqsave(&data->lock, flags);
-
- reg = readl(reg_addr);
- if (assert)
- writel(reg & ~BIT(offset), reg_addr);
- else
- writel(reg | BIT(offset), reg_addr);
-
- spin_unlock_irqrestore(&data->lock, flags);
-
- return 0;
+ return regmap_update_bits(data->map, offset,
+ BIT(bit), assert ? 0 : BIT(bit));
}

static int meson_reset_assert(struct reset_controller_dev *rcdev,
@@ -113,30 +109,42 @@ static const struct of_device_id meson_reset_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, meson_reset_dt_ids);

+static const struct regmap_config regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+};
+
static int meson_reset_probe(struct platform_device *pdev)
{
+ struct device *dev = &pdev->dev;
struct meson_reset *data;
+ void __iomem *base;

- data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;

- data->reg_base = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(data->reg_base))
- return PTR_ERR(data->reg_base);
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return PTR_ERR(base);

- data->param = of_device_get_match_data(&pdev->dev);
+ data->param = of_device_get_match_data(dev);
if (!data->param)
return -ENODEV;

- spin_lock_init(&data->lock);
+ data->map = devm_regmap_init_mmio(dev, base, &regmap_config);
+ if (IS_ERR(data->map))
+ return dev_err_probe(dev, PTR_ERR(data->map),
+ "can't init regmap mmio region\n");

data->rcdev.owner = THIS_MODULE;
- data->rcdev.nr_resets = data->param->reg_count * BITS_PER_REG;
+ data->rcdev.nr_resets = data->param->reg_count * BITS_PER_BYTE
+ * regmap_config.reg_stride;
data->rcdev.ops = &meson_reset_ops;
- data->rcdev.of_node = pdev->dev.of_node;
+ data->rcdev.of_node = dev->of_node;

- return devm_reset_controller_register(&pdev->dev, &data->rcdev);
+ return devm_reset_controller_register(dev, &data->rcdev);
}

static struct platform_driver meson_reset_driver = {
--
2.43.0