clk: sprd: set max_register according to mapping range

In sprd clock driver, regmap_config.max_register was set to a fixed value
which is likely larger than the address range configured in device tree,
when reading registers through debugfs it would cause access violation.

Fixes: d41f59fd92f2 ("clk: sprd: Add common infrastructure")
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20230316023624.758204-1-chunyan.zhang@unisoc.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

diff --git a/drivers/clk/sprd/common.c b/drivers/clk/sprd/common.c
index ce81e4087a8fce2e8d2239e6d706de7f33b24c7d..2bfbab8db94bf54dcb164012d79d45b0b0df3d2f 100644 (file)
--- a/drivers/clk/sprd/common.c
+++ b/drivers/clk/sprd/common.c
@@ -17,7 +17,6 @@ static const struct regmap_config sprdclk_regmap_config = {
        .reg_bits       = 32,
        .reg_stride     = 4,
        .val_bits       = 32,
-       .max_register   = 0xffff,
        .fast_io        = true,
 };
 
@@ -43,6 +42,8 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
        struct device *dev = &pdev->dev;
        struct device_node *node = dev->of_node, *np;
        struct regmap *regmap;
+       struct resource *res;
+       struct regmap_config reg_config = sprdclk_regmap_config;
 
        if (of_find_property(node, "sprd,syscon", NULL)) {
                regmap = syscon_regmap_lookup_by_phandle(node, "sprd,syscon");
@@ -59,12 +60,14 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
                        return PTR_ERR(regmap);
                }
        } else {
-               base = devm_platform_ioremap_resource(pdev, 0);
+               base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
                if (IS_ERR(base))
                        return PTR_ERR(base);
 
+               reg_config.max_register = resource_size(res) - reg_config.reg_stride;
+
                regmap = devm_regmap_init_mmio(&pdev->dev, base,
-                                              &sprdclk_regmap_config);
+                                              &reg_config);
                if (IS_ERR(regmap)) {
                        pr_err("failed to init regmap\n");
                        return PTR_ERR(regmap);