Linux-libre 4.5-gnu

1 files changed, 317 insertions, 0 deletions

diff --git a/drivers/soc/fsl/qe/gpio.c b/drivers/soc/fsl/qe/gpio.c
new file mode 100644
index 000000000..aa5c11acf
--- /dev/null
+++ b/drivers/soc/fsl/qe/gpio.c
@@ -0,0 +1,317 @@
+/*
+ * QUICC Engine GPIOs
+ *
+ * Copyright (c) MontaVista Software, Inc. 2008.
+ *
+ * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <soc/fsl/qe/qe.h>
+
+struct qe_gpio_chip {
+	struct of_mm_gpio_chip mm_gc;
+	spinlock_t lock;
+
+	unsigned long pin_flags[QE_PIO_PINS];
+#define QE_PIN_REQUESTED 0
+
+	/* shadowed data register to clear/set bits safely */
+	u32 cpdata;
+
+	/* saved_regs used to restore dedicated functions */
+	struct qe_pio_regs saved_regs;
+};
+
+static inline struct qe_gpio_chip *
+to_qe_gpio_chip(struct of_mm_gpio_chip *mm_gc)
+{
+	return container_of(mm_gc, struct qe_gpio_chip, mm_gc);
+}
+
+static void qe_gpio_save_regs(struct of_mm_gpio_chip *mm_gc)
+{
+	struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+	struct qe_pio_regs __iomem *regs = mm_gc->regs;
+
+	qe_gc->cpdata = in_be32(&regs->cpdata);
+	qe_gc->saved_regs.cpdata = qe_gc->cpdata;
+	qe_gc->saved_regs.cpdir1 = in_be32(&regs->cpdir1);
+	qe_gc->saved_regs.cpdir2 = in_be32(&regs->cpdir2);
+	qe_gc->saved_regs.cppar1 = in_be32(&regs->cppar1);
+	qe_gc->saved_regs.cppar2 = in_be32(&regs->cppar2);
+	qe_gc->saved_regs.cpodr = in_be32(&regs->cpodr);
+}
+
+static int qe_gpio_get(struct gpio_chip *gc, unsigned int gpio)
+{
+	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+	struct qe_pio_regs __iomem *regs = mm_gc->regs;
+	u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio);
+
+	return in_be32(&regs->cpdata) & pin_mask;
+}
+
+static void qe_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+	struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+	struct qe_pio_regs __iomem *regs = mm_gc->regs;
+	unsigned long flags;
+	u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio);
+
+	spin_lock_irqsave(&qe_gc->lock, flags);
+
+	if (val)
+		qe_gc->cpdata |= pin_mask;
+	else
+		qe_gc->cpdata &= ~pin_mask;
+
+	out_be32(&regs->cpdata, qe_gc->cpdata);
+
+	spin_unlock_irqrestore(&qe_gc->lock, flags);
+}
+
+static int qe_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
+{
+	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+	struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+	unsigned long flags;
+
+	spin_lock_irqsave(&qe_gc->lock, flags);
+
+	__par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_IN, 0, 0, 0);
+
+	spin_unlock_irqrestore(&qe_gc->lock, flags);
+
+	return 0;
+}
+
+static int qe_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+	struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+	unsigned long flags;
+
+	qe_gpio_set(gc, gpio, val);
+
+	spin_lock_irqsave(&qe_gc->lock, flags);
+
+	__par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_OUT, 0, 0, 0);
+
+	spin_unlock_irqrestore(&qe_gc->lock, flags);
+
+	return 0;
+}
+
+struct qe_pin {
+	/*
+	 * The qe_gpio_chip name is unfortunate, we should change that to
+	 * something like qe_pio_controller. Someday.
+	 */
+	struct qe_gpio_chip *controller;
+	int num;
+};
+
+/**
+ * qe_pin_request - Request a QE pin
+ * @np:		device node to get a pin from
+ * @index:	index of a pin in the device tree
+ * Context:	non-atomic
+ *
+ * This function return qe_pin so that you could use it with the rest of
+ * the QE Pin Multiplexing API.
+ */
+struct qe_pin *qe_pin_request(struct device_node *np, int index)
+{
+	struct qe_pin *qe_pin;
+	struct gpio_chip *gc;
+	struct of_mm_gpio_chip *mm_gc;
+	struct qe_gpio_chip *qe_gc;
+	int err;
+	unsigned long flags;
+
+	qe_pin = kzalloc(sizeof(*qe_pin), GFP_KERNEL);
+	if (!qe_pin) {
+		pr_debug("%s: can't allocate memory\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	err = of_get_gpio(np, index);
+	if (err < 0)
+		goto err0;
+	gc = gpio_to_chip(err);
+	if (WARN_ON(!gc))
+		goto err0;
+
+	if (!of_device_is_compatible(gc->of_node, "fsl,mpc8323-qe-pario-bank")) {
+		pr_debug("%s: tried to get a non-qe pin\n", __func__);
+		err = -EINVAL;
+		goto err0;
+	}
+
+	mm_gc = to_of_mm_gpio_chip(gc);
+	qe_gc = to_qe_gpio_chip(mm_gc);
+
+	spin_lock_irqsave(&qe_gc->lock, flags);
+
+	err -= gc->base;
+	if (test_and_set_bit(QE_PIN_REQUESTED, &qe_gc->pin_flags[err]) == 0) {
+		qe_pin->controller = qe_gc;
+		qe_pin->num = err;
+		err = 0;
+	} else {
+		err = -EBUSY;
+	}
+
+	spin_unlock_irqrestore(&qe_gc->lock, flags);
+
+	if (!err)
+		return qe_pin;
+err0:
+	kfree(qe_pin);
+	pr_debug("%s failed with status %d\n", __func__, err);
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL(qe_pin_request);
+
+/**
+ * qe_pin_free - Free a pin
+ * @qe_pin:	pointer to the qe_pin structure
+ * Context:	any
+ *
+ * This function frees the qe_pin structure and makes a pin available
+ * for further qe_pin_request() calls.
+ */
+void qe_pin_free(struct qe_pin *qe_pin)
+{
+	struct qe_gpio_chip *qe_gc = qe_pin->controller;
+	unsigned long flags;
+	const int pin = qe_pin->num;
+
+	spin_lock_irqsave(&qe_gc->lock, flags);
+	test_and_clear_bit(QE_PIN_REQUESTED, &qe_gc->pin_flags[pin]);
+	spin_unlock_irqrestore(&qe_gc->lock, flags);
+
+	kfree(qe_pin);
+}
+EXPORT_SYMBOL(qe_pin_free);
+
+/**
+ * qe_pin_set_dedicated - Revert a pin to a dedicated peripheral function mode
+ * @qe_pin:	pointer to the qe_pin structure
+ * Context:	any
+ *
+ * This function resets a pin to a dedicated peripheral function that
+ * has been set up by the firmware.
+ */
+void qe_pin_set_dedicated(struct qe_pin *qe_pin)
+{
+	struct qe_gpio_chip *qe_gc = qe_pin->controller;
+	struct qe_pio_regs __iomem *regs = qe_gc->mm_gc.regs;
+	struct qe_pio_regs *sregs = &qe_gc->saved_regs;
+	int pin = qe_pin->num;
+	u32 mask1 = 1 << (QE_PIO_PINS - (pin + 1));
+	u32 mask2 = 0x3 << (QE_PIO_PINS - (pin % (QE_PIO_PINS / 2) + 1) * 2);
+	bool second_reg = pin > (QE_PIO_PINS / 2) - 1;
+	unsigned long flags;
+
+	spin_lock_irqsave(&qe_gc->lock, flags);
+
+	if (second_reg) {
+		clrsetbits_be32(&regs->cpdir2, mask2, sregs->cpdir2 & mask2);
+		clrsetbits_be32(&regs->cppar2, mask2, sregs->cppar2 & mask2);
+	} else {
+		clrsetbits_be32(&regs->cpdir1, mask2, sregs->cpdir1 & mask2);
+		clrsetbits_be32(&regs->cppar1, mask2, sregs->cppar1 & mask2);
+	}
+
+	if (sregs->cpdata & mask1)
+		qe_gc->cpdata |= mask1;
+	else
+		qe_gc->cpdata &= ~mask1;
+
+	out_be32(&regs->cpdata, qe_gc->cpdata);
+	clrsetbits_be32(&regs->cpodr, mask1, sregs->cpodr & mask1);
+
+	spin_unlock_irqrestore(&qe_gc->lock, flags);
+}
+EXPORT_SYMBOL(qe_pin_set_dedicated);
+
+/**
+ * qe_pin_set_gpio - Set a pin to the GPIO mode
+ * @qe_pin:	pointer to the qe_pin structure
+ * Context:	any
+ *
+ * This function sets a pin to the GPIO mode.
+ */
+void qe_pin_set_gpio(struct qe_pin *qe_pin)
+{
+	struct qe_gpio_chip *qe_gc = qe_pin->controller;
+	struct qe_pio_regs __iomem *regs = qe_gc->mm_gc.regs;
+	unsigned long flags;
+
+	spin_lock_irqsave(&qe_gc->lock, flags);
+
+	/* Let's make it input by default, GPIO API is able to change that. */
+	__par_io_config_pin(regs, qe_pin->num, QE_PIO_DIR_IN, 0, 0, 0);
+
+	spin_unlock_irqrestore(&qe_gc->lock, flags);
+}
+EXPORT_SYMBOL(qe_pin_set_gpio);
+
+static int __init qe_add_gpiochips(void)
+{
+	struct device_node *np;
+
+	for_each_compatible_node(np, NULL, "fsl,mpc8323-qe-pario-bank") {
+		int ret;
+		struct qe_gpio_chip *qe_gc;
+		struct of_mm_gpio_chip *mm_gc;
+		struct gpio_chip *gc;
+
+		qe_gc = kzalloc(sizeof(*qe_gc), GFP_KERNEL);
+		if (!qe_gc) {
+			ret = -ENOMEM;
+			goto err;
+		}
+
+		spin_lock_init(&qe_gc->lock);
+
+		mm_gc = &qe_gc->mm_gc;
+		gc = &mm_gc->gc;
+
+		mm_gc->save_regs = qe_gpio_save_regs;
+		gc->ngpio = QE_PIO_PINS;
+		gc->direction_input = qe_gpio_dir_in;
+		gc->direction_output = qe_gpio_dir_out;
+		gc->get = qe_gpio_get;
+		gc->set = qe_gpio_set;
+
+		ret = of_mm_gpiochip_add(np, mm_gc);
+		if (ret)
+			goto err;
+		continue;
+err:
+		pr_err("%s: registration failed with status %d\n",
+		       np->full_name, ret);
+		kfree(qe_gc);
+		/* try others anyway */
+	}
+	return 0;
+}
+arch_initcall(qe_add_gpiochips);