clocksource: sh_tmu: Add DT support

Document DT bindings and parse them in the TMU driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Simon Horman <horms+renesas@verge.net.au>
(cherry picked from commit 3e29b5543f9250bb358169cff0594f58284ece74)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

diff --git a/Documentation/devicetree/bindings/timer/renesas,tmu.txt b/Documentation/devicetree/bindings/timer/renesas,tmu.txt
new file mode 100644 (file)
index 0000000..425d0c5
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/renesas,tmu.txt
@@ -0,0 +1,39 @@
+* Renesas R-Car Timer Unit (TMU)
+
+The TMU is a 32-bit timer/counter with configurable clock inputs and
+programmable compare match.
+
+Channels share hardware resources but their counter and compare match value
+are independent. The TMU hardware supports up to three channels.
+
+Required Properties:
+
+  - compatible: must contain "renesas,tmu"
+
+  - reg: base address and length of the registers block for the timer module.
+
+  - interrupts: interrupt-specifier for the timer, one per channel.
+
+  - clocks: a list of phandle + clock-specifier pairs, one for each entry
+    in clock-names.
+  - clock-names: must contain "fck" for the functional clock.
+
+Optional Properties:
+
+  - #renesas,channels: number of channels implemented by the timer, must be 2
+    or 3 (if not specified the value defaults to 3).
+
+
+Example: R8A7779 (R-Car H1) TMU0 node
+
+       tmu0: timer@ffd80000 {
+               compatible = "renesas,tmu";
+               reg = <0xffd80000 0x30>;
+               interrupts = <0 32 IRQ_TYPE_LEVEL_HIGH>,
+                            <0 33 IRQ_TYPE_LEVEL_HIGH>,
+                            <0 34 IRQ_TYPE_LEVEL_HIGH>;
+               clocks = <&mstp0_clks R8A7779_CLK_TMU0>;
+               clock-names = "fck";
+
+               #renesas,channels = <3>;
+       };

diff --git a/drivers/clocksource/sh_tmu.c b/drivers/clocksource/sh_tmu.c
index 560a31a..0f665b8 100644 (file)
--- a/drivers/clocksource/sh_tmu.c
+++ b/drivers/clocksource/sh_tmu.c
@@ -24,6 +24,7 @@
 #include <linux/ioport.h>
 #include <linux/irq.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
@@ -509,23 +510,48 @@ static int sh_tmu_map_memory(struct sh_tmu_device *tmu)
        return 0;
 }
 
+static int sh_tmu_parse_dt(struct sh_tmu_device *tmu)
+{
+       struct device_node *np = tmu->pdev->dev.of_node;
+
+       tmu->model = SH_TMU;
+       tmu->num_channels = 3;
+
+       of_property_read_u32(np, "#renesas,channels", &tmu->num_channels);
+
+       if (tmu->num_channels != 2 && tmu->num_channels != 3) {
+               dev_err(&tmu->pdev->dev, "invalid number of channels %u\n",
+                       tmu->num_channels);
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
 static int sh_tmu_setup(struct sh_tmu_device *tmu, struct platform_device *pdev)
 {
-       struct sh_timer_config *cfg = pdev->dev.platform_data;
-       const struct platform_device_id *id = pdev->id_entry;
        unsigned int i;
        int ret;
 
-       if (!cfg) {
-               dev_err(&tmu->pdev->dev, "missing platform data\n");
-               return -ENXIO;
-       }
-
        tmu->pdev = pdev;
-       tmu->model = id->driver_data;
 
        raw_spin_lock_init(&tmu->lock);
 
+       if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) {
+               ret = sh_tmu_parse_dt(tmu);
+               if (ret < 0)
+                       return ret;
+       } else if (pdev->dev.platform_data) {
+               const struct platform_device_id *id = pdev->id_entry;
+               struct sh_timer_config *cfg = pdev->dev.platform_data;
+
+               tmu->model = id->driver_data;
+               tmu->num_channels = hweight8(cfg->channels_mask);
+       } else {
+               dev_err(&tmu->pdev->dev, "missing platform data\n");
+               return -ENXIO;
+       }
+
        /* Get hold of clock. */
        tmu->clk = clk_get(&tmu->pdev->dev, "fck");
        if (IS_ERR(tmu->clk)) {
@@ -545,8 +571,6 @@ static int sh_tmu_setup(struct sh_tmu_device *tmu, struct platform_device *pdev)
        }
 
        /* Allocate and setup the channels. */
-       tmu->num_channels = hweight8(cfg->channels_mask);
-
        tmu->channels = kzalloc(sizeof(*tmu->channels) * tmu->num_channels,
                                GFP_KERNEL);
        if (tmu->channels == NULL) {
@@ -628,11 +652,18 @@ static const struct platform_device_id sh_tmu_id_table[] = {
 };
 MODULE_DEVICE_TABLE(platform, sh_tmu_id_table);
 
+static const struct of_device_id sh_tmu_of_table[] __maybe_unused = {
+       { .compatible = "renesas,tmu" },
+       { }
+};
+MODULE_DEVICE_TABLE(of, sh_tmu_of_table);
+
 static struct platform_driver sh_tmu_device_driver = {
        .probe          = sh_tmu_probe,
        .remove         = sh_tmu_remove,
        .driver         = {
                .name   = "sh_tmu",
+               .of_match_table = of_match_ptr(sh_tmu_of_table),
        },
        .id_table       = sh_tmu_id_table,
 };