MIPS: ralink: Add support for reset-controller API

Add a helper for reseting different devices on the SoC.

Signed-off-by: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5804/
Patchwork: https://patchwork.linux-mips.org/patch/5797/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 24727a0..a1a088b 100644 (file)
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -446,6 +446,8 @@ config RALINK
        select SYS_HAS_EARLY_PRINTK
        select HAVE_MACH_CLKDEV
        select CLKDEV_LOOKUP
+       select ARCH_HAS_RESET_CONTROLLER
+       select RESET_CONTROLLER
 
 config SGI_IP22
        bool "SGI IP22 (Indy/Indigo2)"

diff --git a/arch/mips/ralink/common.h b/arch/mips/ralink/common.h
index 83144c3..42dfd61 100644 (file)
--- a/arch/mips/ralink/common.h
+++ b/arch/mips/ralink/common.h
@@ -46,6 +46,8 @@ extern void ralink_of_remap(void);
 extern void ralink_clk_init(void);
 extern void ralink_clk_add(const char *dev, unsigned long rate);
 
+extern void ralink_rst_init(void);
+
 extern void prom_soc_init(struct ralink_soc_info *soc_info);
 
 __iomem void *plat_of_remap_node(const char *node);

diff --git a/arch/mips/ralink/of.c b/arch/mips/ralink/of.c
index f25ea5b..ce38d11 100644 (file)
--- a/arch/mips/ralink/of.c
+++ b/arch/mips/ralink/of.c
@@ -110,6 +110,9 @@ static int __init plat_of_setup(void)
        if (of_platform_populate(NULL, of_ids, NULL, NULL))
                panic("failed to populate DT\n");
 
+       /* make sure ithat the reset controller is setup early */
+       ralink_rst_init();
+
        return 0;
 }
 

diff --git a/arch/mips/ralink/reset.c b/arch/mips/ralink/reset.c
index 22120e5..55c7ec5 100644 (file)
--- a/arch/mips/ralink/reset.c
+++ b/arch/mips/ralink/reset.c
@@ -10,6 +10,8 @@
 
 #include <linux/pm.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/reset-controller.h>
 
 #include <asm/reboot.h>
 
@@ -19,6 +21,66 @@
 #define SYSC_REG_RESET_CTRL     0x034
 #define RSTCTL_RESET_SYSTEM     BIT(0)
 
+static int ralink_assert_device(struct reset_controller_dev *rcdev,
+                               unsigned long id)
+{
+       u32 val;
+
+       if (id < 8)
+               return -1;
+
+       val = rt_sysc_r32(SYSC_REG_RESET_CTRL);
+       val |= BIT(id);
+       rt_sysc_w32(val, SYSC_REG_RESET_CTRL);
+
+       return 0;
+}
+
+static int ralink_deassert_device(struct reset_controller_dev *rcdev,
+                                 unsigned long id)
+{
+       u32 val;
+
+       if (id < 8)
+               return -1;
+
+       val = rt_sysc_r32(SYSC_REG_RESET_CTRL);
+       val &= ~BIT(id);
+       rt_sysc_w32(val, SYSC_REG_RESET_CTRL);
+
+       return 0;
+}
+
+static int ralink_reset_device(struct reset_controller_dev *rcdev,
+                              unsigned long id)
+{
+       ralink_assert_device(rcdev, id);
+       return ralink_deassert_device(rcdev, id);
+}
+
+static struct reset_control_ops reset_ops = {
+       .reset = ralink_reset_device,
+       .assert = ralink_assert_device,
+       .deassert = ralink_deassert_device,
+};
+
+static struct reset_controller_dev reset_dev = {
+       .ops                    = &reset_ops,
+       .owner                  = THIS_MODULE,
+       .nr_resets              = 32,
+       .of_reset_n_cells       = 1,
+};
+
+void ralink_rst_init(void)
+{
+       reset_dev.of_node = of_find_compatible_node(NULL, NULL,
+                                               "ralink,rt2880-reset");
+       if (!reset_dev.of_node)
+               pr_err("Failed to find reset controller node");
+       else
+               reset_controller_register(&reset_dev);
+}
+
 static void ralink_restart(char *command)
 {
        local_irq_disable();