reset: img: Add Pistachio reset controller driver

Add reset controller driver for Pistachio SoC

Signed-off-by: Damien Horsley <Damien.Horsley@imgtec.com>
Signed-off-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 4d7178e46afad2ceb0a16403a79e9a9d18922e95..a1fc8eda79f3885242dac6292af72299d52a7ad8 100644 (file)
--- 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/reset-pistachio.c b/drivers/reset/reset-pistachio.c
new file mode 100644 (file)
index 0000000..b31cdb0
--- /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 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/include/dt-bindings/reset/pistachio-resets.h b/include/dt-bindings/reset/pistachio-resets.h
new file mode 100644 (file)
index 0000000..60a189b
--- /dev/null
+++ b/include/dt-bindings/reset/pistachio-resets.h
@@ -0,0 +1,36 @@
+/*
+ * This header provides constants for the reset controller
+ * present in the Pistachio SoC
+ */
+
+#ifndef _PISTACHIO_RESETS_H
+#define _PISTACHIO_RESETS_H
+
+#define PISTACHIO_RESET_I2C0           0
+#define PISTACHIO_RESET_I2C1           1
+#define PISTACHIO_RESET_I2C2           2
+#define PISTACHIO_RESET_I2C3           3
+#define PISTACHIO_RESET_I2S_IN         4
+#define PISTACHIO_RESET_PRL_OUT                5
+#define PISTACHIO_RESET_SPDIF_OUT      6
+#define PISTACHIO_RESET_SPI            7
+#define PISTACHIO_RESET_PWM_PDM                8
+#define PISTACHIO_RESET_UART0          9
+#define PISTACHIO_RESET_UART1          10
+#define PISTACHIO_RESET_QSPI           11
+#define PISTACHIO_RESET_MDC            12
+#define PISTACHIO_RESET_SDHOST         13
+#define PISTACHIO_RESET_ETHERNET       14
+#define PISTACHIO_RESET_IR             15
+#define PISTACHIO_RESET_HASH           16
+#define PISTACHIO_RESET_TIMER          17
+#define PISTACHIO_RESET_I2S_OUT                18
+#define PISTACHIO_RESET_SPDIF_IN       19
+#define PISTACHIO_RESET_EVT            20
+#define PISTACHIO_RESET_USB_H          21
+#define PISTACHIO_RESET_USB_PR         22
+#define PISTACHIO_RESET_USB_PHY_PR     23
+#define PISTACHIO_RESET_USB_PHY_PON    24
+#define PISTACHIO_RESET_MAX            24
+
+#endif