[PATCH 3/4] pinctrl: single: omap: Add SoC specific module for wake-up events

[Tony Lindgren <tony@atomide.com>]

For wake-up events from deeper idle modes we need to check the
configured padconf registers for the wake-up bit and then call
the related interrupt handler.

Done in collaboration with Roger Quadros <rogerq@ti.com>.

Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Peter Ujfalusi <peter.ujfalusi@ti.com>
Cc: devicetree-discuss@lists.ozlabs.org
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
---
 drivers/pinctrl/Makefile                          |    3 
 drivers/pinctrl/pinctrl-single-omap.c             |  287 +++++++++++++++++++++
 include/linux/platform_data/pinctrl-single-omap.h |    4 
 3 files changed, 293 insertions(+), 1 deletion(-)
 create mode 100644 drivers/pinctrl/pinctrl-single-omap.c
 create mode 100644 include/linux/platform_data/pinctrl-single-omap.h

diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index 9bdaeb8..abf7f01 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -30,7 +30,8 @@ obj-$(CONFIG_PINCTRL_NOMADIK)	+= pinctrl-nomadik.o
 obj-$(CONFIG_PINCTRL_STN8815)	+= pinctrl-nomadik-stn8815.o
 obj-$(CONFIG_PINCTRL_DB8500)	+= pinctrl-nomadik-db8500.o
 obj-$(CONFIG_PINCTRL_DB8540)	+= pinctrl-nomadik-db8540.o
-obj-$(CONFIG_PINCTRL_SINGLE)	+= pinctrl-single.o
+pcs-$(CONFIG_ARCH_OMAP2PLUS)	+= pinctrl-single-omap.o
+obj-$(CONFIG_PINCTRL_SINGLE)	+= pinctrl-single.o $(pcs-y)
 obj-$(CONFIG_PINCTRL_SIRF)	+= pinctrl-sirf.o
 obj-$(CONFIG_PINCTRL_SUNXI)	+= pinctrl-sunxi.o
 obj-$(CONFIG_PINCTRL_TEGRA)	+= pinctrl-tegra.o
diff --git a/drivers/pinctrl/pinctrl-single-omap.c b/drivers/pinctrl/pinctrl-single-omap.c
new file mode 100644
index 0000000..680cf81
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-single-omap.c
@@ -0,0 +1,287 @@
+/*
+ * pinctrl-single-omap - omap specific wake-up irq handler
+ *
+ * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/pinctrl-single-omap.h>
+#include <linux/pm_runtime.h>
+
+#include "pinctrl-single.h"
+
+#define OMAP_WAKEUP_EN		(1 << 14)
+#define OMAP_WAKEUP_EVENT	(1 << 15)
+#define OMAP_WAKEUP_EVENT_MASK	(OMAP_WAKEUP_EN | OMAP_WAKEUP_EVENT)
+
+struct pcs_omap {
+	unsigned int irq;
+	struct device *dev;
+	struct list_head wakeirqs;
+	struct pcs_soc soc;
+	void (*reconfigure_io_chain)(void);
+	struct mutex mutex;
+};
+
+static int pcs_omap_reg_init(const struct pcs_soc *soc, struct pcs_reg *r)
+{
+	struct pcs_omap *pcso = container_of(soc, struct pcs_omap, soc);
+	struct list_head *pos;
+	struct pcs_reg *pcsoi;
+	int res = 0;
+
+	if (!(r->val & OMAP_WAKEUP_EN))
+		return 0;
+
+	if (r->irq <= 0)
+		return 0;
+
+	mutex_lock(&pcso->mutex);
+	list_for_each(pos, &pcso->wakeirqs) {
+		pcsoi = list_entry(pos, struct pcs_reg, node);
+		if (r->reg == pcsoi->reg) {
+			pcsoi->read = r->read;
+			pcsoi->write = r->write;
+			pcsoi->reg = r->reg;
+			pcsoi->val = r->val;
+			pcsoi->irq = r->irq;
+			pcsoi->gpio = r->gpio;
+			res++;
+			goto out;
+		}
+	}
+	pcsoi = devm_kzalloc(pcso->dev, sizeof(*r), GFP_KERNEL);
+	if (!pcsoi) {
+		mutex_unlock(&pcso->mutex);
+		res = -ENOMEM;
+		goto out;
+	}
+	*pcsoi = *r;
+	list_add_tail(&pcsoi->node, &pcso->wakeirqs);
+
+out:
+	mutex_unlock(&pcso->mutex);
+
+	if (res && pcso->reconfigure_io_chain)
+		pcso->reconfigure_io_chain();
+
+	return res > 0 ? 0 : res;
+}
+
+static int pcs_update_list(const struct pcs_soc *soc, struct pcs_reg *r)
+{
+	struct pcs_omap *pcso = container_of(soc, struct pcs_omap, soc);
+	struct list_head *pos;
+	int changed = 0;
+
+	if (!r->irq)
+		return 0;
+
+	mutex_lock(&pcso->mutex);
+	list_for_each(pos, &pcso->wakeirqs) {
+		struct pcs_reg *pcsoi;
+
+		pcsoi = list_entry(pos, struct pcs_reg, node);
+		if ((r->reg == pcsoi->reg) &&
+		    (r->val != pcsoi->val)) {
+			pcsoi->val = r->val;
+			changed++;
+		}
+	}
+	mutex_unlock(&pcso->mutex);
+
+	if (pcso->reconfigure_io_chain && changed)
+		pcso->reconfigure_io_chain();
+
+	return 0;
+}
+
+static int pcs_omap_enable(const struct pcs_soc *soc, struct pcs_reg *r)
+{
+	return pcs_update_list(soc, r);
+}
+
+static void pcs_omap_disable(const struct pcs_soc *soc, struct pcs_reg *r)
+{
+	pcs_update_list(soc, r);
+}
+
+static irqreturn_t pcs_omap_handle_irq(int irq, void *data)
+{
+	struct pcs_omap *pcso = data;
+	struct list_head *pos;
+	unsigned int wakeirq;
+
+	list_for_each(pos, &pcso->wakeirqs) {
+		struct pcs_reg *pcsoi;
+		u16 val;
+
+		pcsoi = list_entry(pos, struct pcs_reg, node);
+		wakeirq = pcsoi->irq;
+		val = pcsoi->read(pcsoi->reg);
+		if ((val & OMAP_WAKEUP_EVENT_MASK) == OMAP_WAKEUP_EVENT_MASK)
+			generic_handle_irq(wakeirq);
+	}
+
+	if (pcso->reconfigure_io_chain)
+		pcso->reconfigure_io_chain();
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Note that omap2430 has 8-bit padconf registers and uses
+ * the plain pinctrl-single binding.
+ */
+static const struct of_device_id pcs_omap_of_match[] = {
+	{ .compatible = "ti,omap3-padconf", },
+	{ .compatible = "ti,omap4-padconf", },
+	{ .compatible = "ti,omap5-padconf", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, pcs_omap_of_match);
+
+/* SoC glue */
+static bool soc_found;
+static unsigned int soc_irq;
+static void (*soc_reconfigure_io_chain)(void);
+
+/* Fill in the SoC glue */
+static int pcs_omap_soc_probe(struct platform_device *pdev)
+{
+	struct pcs_omap_pdata *pdata = pdev->dev.platform_data;
+
+	if (pdata) {
+		soc_irq = pdata->irq;
+		soc_reconfigure_io_chain = pdata->reconfigure_io_chain;
+		soc_found = true;
+	}
+
+	return 0;
+}
+
+static int pcs_omap_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	struct pcs_omap *pcso;
+	struct pcs_soc *soc;
+	int ret;
+
+	match = of_match_device(pcs_omap_of_match, &pdev->dev);
+	if (!match) {
+		dev_err(&pdev->dev, "no match found\n");
+		return -ENODEV;
+	}
+
+	if (!soc_found) {
+		dev_dbg(&pdev->dev,
+			"%s deferring as SoC glue not yet registered\n",
+			 __func__);
+		return -EPROBE_DEFER;
+	}
+
+	pcso = devm_kzalloc(&pdev->dev, sizeof(*pcso), GFP_KERNEL);
+	if (!pcso)
+		return -ENOMEM;
+
+	pcso->dev = &pdev->dev;
+	mutex_init(&pcso->mutex);
+	INIT_LIST_HEAD(&pcso->wakeirqs);
+	pcso->irq = soc_irq;
+	pcso->reconfigure_io_chain = soc_reconfigure_io_chain;
+	soc = &pcso->soc;
+	soc->reg_init = pcs_omap_reg_init;
+	soc->enable = pcs_omap_enable;
+	soc->disable = pcs_omap_disable;
+	soc->flags = PCS_HAS_FUNCTION_GPIO | PCS_HAS_FUNCTION_IRQ;
+
+	ret = pinctrl_single_probe(pdev, soc);
+	if (ret) {
+		dev_err(&pdev->dev, "could not probe pictrl_single driver: %i\n",
+			ret);
+		return ret;
+	}
+
+	ret = request_irq(soc_irq, pcs_omap_handle_irq,
+			  IRQF_SHARED | IRQF_NO_SUSPEND,
+			  "pinctrl-single-omap", pcso);
+	if (ret) {
+		dev_err(&pdev->dev, "could not get irq%i: %i\n",
+			soc_irq, ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, pcso);
+	pm_runtime_enable(&pdev->dev);
+
+	return 0;
+}
+
+static int pcs_omap_remove(struct platform_device *pdev)
+{
+	struct pcs_omap *pcso = platform_get_drvdata(pdev);
+
+	pinctrl_single_remove(pdev);
+	free_irq(pcso->irq, NULL);
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static struct platform_driver pcs_omap_driver = {
+	.probe		= pcs_omap_probe,
+	.remove		= pcs_omap_remove,
+	.driver		= {
+		.name	= "pinctrl-single-omap",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(pcs_omap_of_match),
+	},
+};
+
+/* Dummy driver for registering SoC glue */
+static struct platform_driver pcs_omap_soc_driver = {
+	.probe = pcs_omap_soc_probe,
+	.driver	= {
+		.name = "pinctrl-single-omap-soc",
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init pcs_omap_init(void)
+{
+	platform_driver_register(&pcs_omap_soc_driver);
+	platform_driver_register(&pcs_omap_driver);
+
+	return 0;
+}
+module_init(pcs_omap_init);
+
+static void __exit pcs_omap_exit(void)
+{
+	platform_driver_unregister(&pcs_omap_driver);
+	platform_driver_unregister(&pcs_omap_soc_driver);
+}
+module_exit(pcs_omap_exit);
+
+MODULE_ALIAS("platform: pinctrl-single-omap");
+MODULE_AUTHOR("Texas Instruments Inc.");
+MODULE_DESCRIPTION("pinctrl-single-omap driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/platform_data/pinctrl-single-omap.h b/include/linux/platform_data/pinctrl-single-omap.h
new file mode 100644
index 0000000..bd92efc
--- /dev/null
+++ b/include/linux/platform_data/pinctrl-single-omap.h
@@ -0,0 +1,4 @@
+struct pcs_omap_pdata {
+	int irq;
+	void (*reconfigure_io_chain)(void);
+};