11 files changed, 170 insertions, 18 deletions

diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 4d7178e46afa..a1fc8eda79f3 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -2,6 +2,7 @@ obj-y += core.o
 obj-$(CONFIG_ARCH_LPC18XX) += reset-lpc18xx.o
 obj-$(CONFIG_ARCH_SOCFPGA) += reset-socfpga.o
 obj-$(CONFIG_ARCH_BERLIN) += reset-berlin.o
+obj-$(CONFIG_MACH_PISTACHIO) += reset-pistachio.o
 obj-$(CONFIG_ARCH_SUNXI) += reset-sunxi.o
 obj-$(CONFIG_ARCH_STI) += sti/
 obj-$(CONFIG_ARCH_HISI) += hisilicon/
diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index 87376638948d..f15f150b79da 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -45,9 +45,6 @@ struct reset_control {
 static int of_reset_simple_xlate(struct reset_controller_dev *rcdev,
                           const struct of_phandle_args *reset_spec)
 {
-        if (WARN_ON(reset_spec->args_count != rcdev->of_reset_n_cells))
-                return -EINVAL;
-
         if (reset_spec->args[0] >= rcdev->nr_resets)
                 return -EINVAL;
 
@@ -152,7 +149,7 @@ EXPORT_SYMBOL_GPL(reset_control_status);
 struct reset_control *of_reset_control_get_by_index(struct device_node *node,
                                            int index)
 {
-        struct reset_control *rstc = ERR_PTR(-EPROBE_DEFER);
+        struct reset_control *rstc;
         struct reset_controller_dev *r, *rcdev;
         struct of_phandle_args args;
         int rstc_id;
@@ -178,6 +175,11 @@ struct reset_control *of_reset_control_get_by_index(struct device_node *node,
                 return ERR_PTR(-EPROBE_DEFER);
         }
 
+        if (WARN_ON(args.args_count != rcdev->of_reset_n_cells)) {
+                mutex_unlock(&reset_controller_list_mutex);
+                return ERR_PTR(-EINVAL);
+        }
+
         rstc_id = rcdev->of_xlate(rcdev, &args);
         if (rstc_id < 0) {
                 mutex_unlock(&reset_controller_list_mutex);
diff --git a/drivers/reset/hisilicon/hi6220_reset.c b/drivers/reset/hisilicon/hi6220_reset.c
index 7787a9b1cc67..8f55fd4a2630 100644
--- a/drivers/reset/hisilicon/hi6220_reset.c
+++ b/drivers/reset/hisilicon/hi6220_reset.c
@@ -57,7 +57,7 @@ static int hi6220_reset_deassert(struct reset_controller_dev *rc_dev,
         return 0;
 }
 
-static struct reset_control_ops hi6220_reset_ops = {
+static const struct reset_control_ops hi6220_reset_ops = {
         .assert = hi6220_reset_assert,
         .deassert = hi6220_reset_deassert,
 };
@@ -83,9 +83,7 @@ static int hi6220_reset_probe(struct platform_device *pdev)
         data->rc_dev.ops = &hi6220_reset_ops;
         data->rc_dev.of_node = pdev->dev.of_node;
 
-        reset_controller_register(&data->rc_dev);
-
-        return 0;
+        return reset_controller_register(&data->rc_dev);
 }
 
 static const struct of_device_id hi6220_reset_match[] = {
diff --git a/drivers/reset/reset-ath79.c b/drivers/reset/reset-ath79.c
index 692fc890e94b..ccb940a8d9fb 100644
--- a/drivers/reset/reset-ath79.c
+++ b/drivers/reset/reset-ath79.c
@@ -70,7 +70,7 @@ static int ath79_reset_status(struct reset_controller_dev *rcdev,
         return !!(val & BIT(id));
 }
 
-static struct reset_control_ops ath79_reset_ops = {
+static const struct reset_control_ops ath79_reset_ops = {
         .assert = ath79_reset_assert,
         .deassert = ath79_reset_deassert,
         .status = ath79_reset_status,
diff --git a/drivers/reset/reset-berlin.c b/drivers/reset/reset-berlin.c
index 970b1ad60293..369f3917fd8e 100644
--- a/drivers/reset/reset-berlin.c
+++ b/drivers/reset/reset-berlin.c
@@ -46,7 +46,7 @@ static int berlin_reset_reset(struct reset_controller_dev *rcdev,
         return 0;
 }
 
-static struct reset_control_ops berlin_reset_ops = {
+static const struct reset_control_ops berlin_reset_ops = {
         .reset  = berlin_reset_reset,
 };
 
@@ -55,9 +55,6 @@ static int berlin_reset_xlate(struct reset_controller_dev *rcdev,
 {
         unsigned offset, bit;
 
-        if (WARN_ON(reset_spec->args_count != rcdev->of_reset_n_cells))
-                return -EINVAL;
-
         offset = reset_spec->args[0];
         bit = reset_spec->args[1];
 
diff --git a/drivers/reset/reset-lpc18xx.c b/drivers/reset/reset-lpc18xx.c
index 70922e9ac27f..3b8a4f5a1ff6 100644
--- a/drivers/reset/reset-lpc18xx.c
+++ b/drivers/reset/reset-lpc18xx.c
@@ -136,7 +136,7 @@ static int lpc18xx_rgu_status(struct reset_controller_dev *rcdev,
         return !(readl(rc->base + offset) & bit);
 }
 
-static struct reset_control_ops lpc18xx_rgu_ops = {
+static const struct reset_control_ops lpc18xx_rgu_ops = {
         .reset          = lpc18xx_rgu_reset,
         .assert         = lpc18xx_rgu_assert,
         .deassert       = lpc18xx_rgu_deassert,
diff --git a/drivers/reset/reset-pistachio.c b/drivers/reset/reset-pistachio.c
new file mode 100644
index 000000000000..72a97a15a4c8
--- /dev/null
+++ b/drivers/reset/reset-pistachio.c
@@ -0,0 +1,154 @@
+/*
+ * Pistachio SoC Reset Controller driver
+ *
+ * Copyright (C) 2015 Imagination Technologies Ltd.
+ *
+ * Author: Damien Horsley <Damien.Horsley@imgtec.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+#include <linux/mfd/syscon.h>
+
+#include <dt-bindings/reset/pistachio-resets.h>
+
+#define PISTACHIO_SOFT_RESET            0
+
+struct pistachio_reset_data {
+        struct reset_controller_dev     rcdev;
+        struct regmap                   *periph_regs;
+};
+
+static inline int pistachio_reset_shift(unsigned long id)
+{
+        switch (id) {
+        case PISTACHIO_RESET_I2C0:
+        case PISTACHIO_RESET_I2C1:
+        case PISTACHIO_RESET_I2C2:
+        case PISTACHIO_RESET_I2C3:
+        case PISTACHIO_RESET_I2S_IN:
+        case PISTACHIO_RESET_PRL_OUT:
+        case PISTACHIO_RESET_SPDIF_OUT:
+        case PISTACHIO_RESET_SPI:
+        case PISTACHIO_RESET_PWM_PDM:
+        case PISTACHIO_RESET_UART0:
+        case PISTACHIO_RESET_UART1:
+        case PISTACHIO_RESET_QSPI:
+        case PISTACHIO_RESET_MDC:
+        case PISTACHIO_RESET_SDHOST:
+        case PISTACHIO_RESET_ETHERNET:
+        case PISTACHIO_RESET_IR:
+        case PISTACHIO_RESET_HASH:
+        case PISTACHIO_RESET_TIMER:
+                return id;
+        case PISTACHIO_RESET_I2S_OUT:
+        case PISTACHIO_RESET_SPDIF_IN:
+        case PISTACHIO_RESET_EVT:
+                return id + 6;
+        case PISTACHIO_RESET_USB_H:
+        case PISTACHIO_RESET_USB_PR:
+        case PISTACHIO_RESET_USB_PHY_PR:
+        case PISTACHIO_RESET_USB_PHY_PON:
+                return id + 7;
+        default:
+                return -EINVAL;
+        }
+}
+
+static int pistachio_reset_assert(struct reset_controller_dev *rcdev,
+                                  unsigned long id)
+{
+        struct pistachio_reset_data *rd;
+        u32 mask;
+        int shift;
+
+        rd = container_of(rcdev, struct pistachio_reset_data, rcdev);
+        shift = pistachio_reset_shift(id);
+        if (shift < 0)
+                return shift;
+        mask = BIT(shift);
+
+        return regmap_update_bits(rd->periph_regs, PISTACHIO_SOFT_RESET,
+                                  mask, mask);
+}
+
+static int pistachio_reset_deassert(struct reset_controller_dev *rcdev,
+                                    unsigned long id)
+{
+        struct pistachio_reset_data *rd;
+        u32 mask;
+        int shift;
+
+        rd = container_of(rcdev, struct pistachio_reset_data, rcdev);
+        shift = pistachio_reset_shift(id);
+        if (shift < 0)
+                return shift;
+        mask = BIT(shift);
+
+        return regmap_update_bits(rd->periph_regs, PISTACHIO_SOFT_RESET,
+                                  mask, 0);
+}
+
+static const struct reset_control_ops pistachio_reset_ops = {
+        .assert         = pistachio_reset_assert,
+        .deassert       = pistachio_reset_deassert,
+};
+
+static int pistachio_reset_probe(struct platform_device *pdev)
+{
+        struct pistachio_reset_data *rd;
+        struct device *dev = &pdev->dev;
+        struct device_node *np = pdev->dev.of_node;
+
+        rd = devm_kzalloc(dev, sizeof(*rd), GFP_KERNEL);
+        if (!rd)
+                return -ENOMEM;
+
+        rd->periph_regs = syscon_node_to_regmap(np->parent);
+        if (IS_ERR(rd->periph_regs))
+                return PTR_ERR(rd->periph_regs);
+
+        rd->rcdev.owner = THIS_MODULE;
+        rd->rcdev.nr_resets = PISTACHIO_RESET_MAX + 1;
+        rd->rcdev.ops = &pistachio_reset_ops;
+        rd->rcdev.of_node = np;
+
+        return reset_controller_register(&rd->rcdev);
+}
+
+static int pistachio_reset_remove(struct platform_device *pdev)
+{
+        struct pistachio_reset_data *data = platform_get_drvdata(pdev);
+
+        reset_controller_unregister(&data->rcdev);
+
+        return 0;
+}
+
+static const struct of_device_id pistachio_reset_dt_ids[] = {
+         { .compatible = "img,pistachio-reset", },
+         { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, pistachio_reset_dt_ids);
+
+static struct platform_driver pistachio_reset_driver = {
+        .probe  = pistachio_reset_probe,
+        .remove = pistachio_reset_remove,
+        .driver = {
+                .name           = "pistachio-reset",
+                .of_match_table = pistachio_reset_dt_ids,
+        },
+};
+module_platform_driver(pistachio_reset_driver);
+
+MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
+MODULE_DESCRIPTION("Pistacho Reset Controller Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/reset/reset-socfpga.c b/drivers/reset/reset-socfpga.c
index b7d773d9248c..cd05a7032b17 100644
--- a/drivers/reset/reset-socfpga.c
+++ b/drivers/reset/reset-socfpga.c
@@ -90,7 +90,7 @@ static int socfpga_reset_status(struct reset_controller_dev *rcdev,
         return !(reg & BIT(offset));
 }
 
-static struct reset_control_ops socfpga_reset_ops = {
+static const struct reset_control_ops socfpga_reset_ops = {
         .assert         = socfpga_reset_assert,
         .deassert       = socfpga_reset_deassert,
         .status         = socfpga_reset_status,
diff --git a/drivers/reset/reset-sunxi.c b/drivers/reset/reset-sunxi.c
index 8d41a18da17f..677f86555212 100644
--- a/drivers/reset/reset-sunxi.c
+++ b/drivers/reset/reset-sunxi.c
@@ -70,7 +70,7 @@ static int sunxi_reset_deassert(struct reset_controller_dev *rcdev,
         return 0;
 }
 
-static struct reset_control_ops sunxi_reset_ops = {
+static const struct reset_control_ops sunxi_reset_ops = {
         .assert         = sunxi_reset_assert,
         .deassert       = sunxi_reset_deassert,
 };
diff --git a/drivers/reset/reset-zynq.c b/drivers/reset/reset-zynq.c
index c6b3cd8b40ad..a7e87bc45885 100644
--- a/drivers/reset/reset-zynq.c
+++ b/drivers/reset/reset-zynq.c
@@ -86,7 +86,7 @@ static int zynq_reset_status(struct reset_controller_dev *rcdev,
         return !!(reg & BIT(offset));
 }
 
-static struct reset_control_ops zynq_reset_ops = {
+static const struct reset_control_ops zynq_reset_ops = {
         .assert         = zynq_reset_assert,
         .deassert       = zynq_reset_deassert,
         .status         = zynq_reset_status,
diff --git a/drivers/reset/sti/reset-syscfg.c b/drivers/reset/sti/reset-syscfg.c
index 1600cc7557f5..9bd57a5eee72 100644
--- a/drivers/reset/sti/reset-syscfg.c
+++ b/drivers/reset/sti/reset-syscfg.c
@@ -134,7 +134,7 @@ static int syscfg_reset_status(struct reset_controller_dev *rcdev,
         return rst->active_low ? !ret_val : !!ret_val;
 }
 
-static struct reset_control_ops syscfg_reset_ops = {
+static const struct reset_control_ops syscfg_reset_ops = {
         .reset    = syscfg_reset_dev,
         .assert   = syscfg_reset_assert,
         .deassert = syscfg_reset_deassert,