[PATCH net-next v2 14/15] soc: sunxi: export a regmap for EMAC clock reg on A64

Chen-Yu Tsai
2018-05-01T16:12:26Z

From: Icenowy Zheng <icenowy@aosc.io>

The A64 SRAM controller memory zone has a EMAC clock register, which is
needed by the Ethernet MAC driver (dwmac-sun8i).

Export a regmap for this register on A64.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
[wens@csie.org: export whole address range with only EMAC register
accessible and drop regmap name]
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
drivers/soc/sunxi/sunxi_sram.c | 57 ++++++++++++++++++++++++++++++++--
1 file changed, 55 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/sunxi/sunxi_sram.c b/drivers/soc/sunxi/sunxi_sram.c
index 882be5ed7e84..eec7fc6e9f66 100644
--- a/drivers/soc/sunxi/sunxi_sram.c
+++ b/drivers/soc/sunxi/sunxi_sram.c
@@ -17,6 +17,7 @@
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>

#include <linux/soc/sunxi/sunxi_sram.h>

@@ -281,13 +282,51 @@ int sunxi_sram_release(struct device *dev)
}
EXPORT_SYMBOL(sunxi_sram_release);

+struct sunxi_sramc_variant {
+ bool has_emac_clock;
+};
+
+static const struct sunxi_sramc_variant sun4i_a10_sramc_variant = {
+ /* Nothing special */
+};
+
+static const struct sunxi_sramc_variant sun50i_a64_sramc_variant = {
+ .has_emac_clock = true,
+};
+
+#define SUNXI_SRAM_EMAC_CLOCK_REG 0x30
+static bool sunxi_sram_regmap_accessible_reg(struct device *dev,
+ unsigned int reg)
+{
+ if (reg == SUNXI_SRAM_EMAC_CLOCK_REG)
+ return true;
+ return false;
+}
+
+static struct regmap_config sunxi_sram_emac_clock_regmap = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ /* last defined register */
+ .max_register = SUNXI_SRAM_EMAC_CLOCK_REG,
+ /* other devices have no business accessing other registers */
+ .readable_reg = sunxi_sram_regmap_accessible_reg,
+ .writeable_reg = sunxi_sram_regmap_accessible_reg,
+};
+
static int sunxi_sram_probe(struct platform_device *pdev)
{
struct resource *res;
struct dentry *d;
+ struct regmap *emac_clock;
+ const struct sunxi_sramc_variant *variant;

sram_dev = &pdev->dev;

+ variant = of_device_get_match_data(&pdev->dev);
+ if (!variant)
+ return -EINVAL;
+
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(base))
@@ -300,12 +339,26 @@ static int sunxi_sram_probe(struct platform_device *pdev)
if (!d)
return -ENOMEM;

+ if (variant->has_emac_clock) {
+ emac_clock = devm_regmap_init_mmio(&pdev->dev, base,
+ &sunxi_sram_emac_clock_regmap);
+
+ if (IS_ERR(emac_clock))
+ return PTR_ERR(emac_clock);
+ }
+
return 0;
}

static const struct of_device_id sunxi_sram_dt_match[] = {
- { .compatible = "allwinner,sun4i-a10-sram-controller" },
- { .compatible = "allwinner,sun50i-a64-sram-controller" },
+ {
+ .compatible = "allwinner,sun4i-a10-sram-controller",
+ .data = &sun4i_a10_sramc_variant,
+ },
+ {
+ .compatible = "allwinner,sun50i-a64-sram-controller",
+ .data = &sun50i_a64_sramc_variant,
+ },
{ },
};
MODULE_DEVICE_TABLE(of, sunxi_sram_dt_match);
--
2.17.0