1 files changed, 510 insertions, 0 deletions

diff --git a/arch/arm/mach-s3c/adc.c b/arch/arm/mach-s3c/adc.c
new file mode 100644
index 000000000000..e35e04417cce
--- /dev/null
+++ b/arch/arm/mach-s3c/adc.c
@@ -0,0 +1,510 @@
+// SPDX-License-Identifier: GPL-1.0+
+//
+// Copyright (c) 2008 Simtec Electronics
+//	http://armlinux.simtec.co.uk/
+//	Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>
+//
+// Samsung ADC device core
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/regulator/consumer.h>
+
+#include <plat/regs-adc.h>
+#include <linux/soc/samsung/s3c-adc.h>
+
+/* This driver is designed to control the usage of the ADC block between
+ * the touchscreen and any other drivers that may need to use it, such as
+ * the hwmon driver.
+ *
+ * Priority will be given to the touchscreen driver, but as this itself is
+ * rate limited it should not starve other requests which are processed in
+ * order that they are received.
+ *
+ * Each user registers to get a client block which uniquely identifies it
+ * and stores information such as the necessary functions to callback when
+ * action is required.
+ */
+
+enum s3c_cpu_type {
+	TYPE_ADCV1, /* S3C24XX */
+	TYPE_ADCV11, /* S3C2443 */
+	TYPE_ADCV12, /* S3C2416, S3C2450 */
+	TYPE_ADCV2, /* S3C64XX */
+	TYPE_ADCV3, /* S5PV210, S5PC110, Exynos4210 */
+};
+
+struct s3c_adc_client {
+	struct platform_device	*pdev;
+	struct list_head	 pend;
+	wait_queue_head_t	*wait;
+
+	unsigned int		 nr_samples;
+	int			 result;
+	unsigned char		 is_ts;
+	unsigned char		 channel;
+
+	void	(*select_cb)(struct s3c_adc_client *c, unsigned selected);
+	void	(*convert_cb)(struct s3c_adc_client *c,
+			      unsigned val1, unsigned val2,
+			      unsigned *samples_left);
+};
+
+struct adc_device {
+	struct platform_device	*pdev;
+	struct platform_device	*owner;
+	struct clk		*clk;
+	struct s3c_adc_client	*cur;
+	struct s3c_adc_client	*ts_pend;
+	void __iomem		*regs;
+	spinlock_t		 lock;
+
+	unsigned int		 prescale;
+
+	int			 irq;
+	struct regulator	*vdd;
+};
+
+static struct adc_device *adc_dev;
+
+static LIST_HEAD(adc_pending);	/* protected by adc_device.lock */
+
+#define adc_dbg(_adc, msg...) dev_dbg(&(_adc)->pdev->dev, msg)
+
+static inline void s3c_adc_convert(struct adc_device *adc)
+{
+	unsigned con = readl(adc->regs + S3C2410_ADCCON);
+
+	con |= S3C2410_ADCCON_ENABLE_START;
+	writel(con, adc->regs + S3C2410_ADCCON);
+}
+
+static inline void s3c_adc_select(struct adc_device *adc,
+				  struct s3c_adc_client *client)
+{
+	unsigned con = readl(adc->regs + S3C2410_ADCCON);
+	enum s3c_cpu_type cpu = platform_get_device_id(adc->pdev)->driver_data;
+
+	client->select_cb(client, 1);
+
+	if (cpu == TYPE_ADCV1 || cpu == TYPE_ADCV2)
+		con &= ~S3C2410_ADCCON_MUXMASK;
+	con &= ~S3C2410_ADCCON_STDBM;
+	con &= ~S3C2410_ADCCON_STARTMASK;
+
+	if (!client->is_ts) {
+		if (cpu == TYPE_ADCV3)
+			writel(client->channel & 0xf, adc->regs + S5P_ADCMUX);
+		else if (cpu == TYPE_ADCV11 || cpu == TYPE_ADCV12)
+			writel(client->channel & 0xf,
+						adc->regs + S3C2443_ADCMUX);
+		else
+			con |= S3C2410_ADCCON_SELMUX(client->channel);
+	}
+
+	writel(con, adc->regs + S3C2410_ADCCON);
+}
+
+static void s3c_adc_dbgshow(struct adc_device *adc)
+{
+	adc_dbg(adc, "CON=%08x, TSC=%08x, DLY=%08x\n",
+		readl(adc->regs + S3C2410_ADCCON),
+		readl(adc->regs + S3C2410_ADCTSC),
+		readl(adc->regs + S3C2410_ADCDLY));
+}
+
+static void s3c_adc_try(struct adc_device *adc)
+{
+	struct s3c_adc_client *next = adc->ts_pend;
+
+	if (!next && !list_empty(&adc_pending)) {
+		next = list_first_entry(&adc_pending,
+					struct s3c_adc_client, pend);
+		list_del(&next->pend);
+	} else
+		adc->ts_pend = NULL;
+
+	if (next) {
+		adc_dbg(adc, "new client is %p\n", next);
+		adc->cur = next;
+		s3c_adc_select(adc, next);
+		s3c_adc_convert(adc);
+		s3c_adc_dbgshow(adc);
+	}
+}
+
+int s3c_adc_start(struct s3c_adc_client *client,
+		  unsigned int channel, unsigned int nr_samples)
+{
+	struct adc_device *adc = adc_dev;
+	unsigned long flags;
+
+	if (!adc) {
+		printk(KERN_ERR "%s: failed to find adc\n", __func__);
+		return -EINVAL;
+	}
+
+	spin_lock_irqsave(&adc->lock, flags);
+
+	if (client->is_ts && adc->ts_pend) {
+		spin_unlock_irqrestore(&adc->lock, flags);
+		return -EAGAIN;
+	}
+
+	client->channel = channel;
+	client->nr_samples = nr_samples;
+
+	if (client->is_ts)
+		adc->ts_pend = client;
+	else
+		list_add_tail(&client->pend, &adc_pending);
+
+	if (!adc->cur)
+		s3c_adc_try(adc);
+
+	spin_unlock_irqrestore(&adc->lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(s3c_adc_start);
+
+static void s3c_convert_done(struct s3c_adc_client *client,
+			     unsigned v, unsigned u, unsigned *left)
+{
+	client->result = v;
+	wake_up(client->wait);
+}
+
+int s3c_adc_read(struct s3c_adc_client *client, unsigned int ch)
+{
+	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake);
+	int ret;
+
+	client->convert_cb = s3c_convert_done;
+	client->wait = &wake;
+	client->result = -1;
+
+	ret = s3c_adc_start(client, ch, 1);
+	if (ret < 0)
+		goto err;
+
+	ret = wait_event_timeout(wake, client->result >= 0, HZ / 2);
+	if (client->result < 0) {
+		ret = -ETIMEDOUT;
+		goto err;
+	}
+
+	client->convert_cb = NULL;
+	return client->result;
+
+err:
+	return ret;
+}
+EXPORT_SYMBOL_GPL(s3c_adc_read);
+
+static void s3c_adc_default_select(struct s3c_adc_client *client,
+				   unsigned select)
+{
+}
+
+struct s3c_adc_client *s3c_adc_register(struct platform_device *pdev,
+					void (*select)(struct s3c_adc_client *client,
+						       unsigned int selected),
+					void (*conv)(struct s3c_adc_client *client,
+						     unsigned d0, unsigned d1,
+						     unsigned *samples_left),
+					unsigned int is_ts)
+{
+	struct s3c_adc_client *client;
+
+	WARN_ON(!pdev);
+
+	if (!select)
+		select = s3c_adc_default_select;
+
+	if (!pdev)
+		return ERR_PTR(-EINVAL);
+
+	client = kzalloc(sizeof(*client), GFP_KERNEL);
+	if (!client)
+		return ERR_PTR(-ENOMEM);
+
+	client->pdev = pdev;
+	client->is_ts = is_ts;
+	client->select_cb = select;
+	client->convert_cb = conv;
+
+	return client;
+}
+EXPORT_SYMBOL_GPL(s3c_adc_register);
+
+void s3c_adc_release(struct s3c_adc_client *client)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&adc_dev->lock, flags);
+
+	/* We should really check that nothing is in progress. */
+	if (adc_dev->cur == client)
+		adc_dev->cur = NULL;
+	if (adc_dev->ts_pend == client)
+		adc_dev->ts_pend = NULL;
+	else {
+		struct list_head *p, *n;
+		struct s3c_adc_client *tmp;
+
+		list_for_each_safe(p, n, &adc_pending) {
+			tmp = list_entry(p, struct s3c_adc_client, pend);
+			if (tmp == client)
+				list_del(&tmp->pend);
+		}
+	}
+
+	if (adc_dev->cur == NULL)
+		s3c_adc_try(adc_dev);
+
+	spin_unlock_irqrestore(&adc_dev->lock, flags);
+	kfree(client);
+}
+EXPORT_SYMBOL_GPL(s3c_adc_release);
+
+static irqreturn_t s3c_adc_irq(int irq, void *pw)
+{
+	struct adc_device *adc = pw;
+	struct s3c_adc_client *client = adc->cur;
+	enum s3c_cpu_type cpu = platform_get_device_id(adc->pdev)->driver_data;
+	unsigned data0, data1;
+
+	if (!client) {
+		dev_warn(&adc->pdev->dev, "%s: no adc pending\n", __func__);
+		goto exit;
+	}
+
+	data0 = readl(adc->regs + S3C2410_ADCDAT0);
+	data1 = readl(adc->regs + S3C2410_ADCDAT1);
+	adc_dbg(adc, "read %d: 0x%04x, 0x%04x\n", client->nr_samples, data0, data1);
+
+	client->nr_samples--;
+
+	if (cpu == TYPE_ADCV1 || cpu == TYPE_ADCV11) {
+		data0 &= 0x3ff;
+		data1 &= 0x3ff;
+	} else {
+		/* S3C2416/S3C64XX/S5P ADC resolution is 12-bit */
+		data0 &= 0xfff;
+		data1 &= 0xfff;
+	}
+
+	if (client->convert_cb)
+		(client->convert_cb)(client, data0, data1, &client->nr_samples);
+
+	if (client->nr_samples > 0) {
+		/* fire another conversion for this */
+
+		client->select_cb(client, 1);
+		s3c_adc_convert(adc);
+	} else {
+		spin_lock(&adc->lock);
+		(client->select_cb)(client, 0);
+		adc->cur = NULL;
+
+		s3c_adc_try(adc);
+		spin_unlock(&adc->lock);
+	}
+
+exit:
+	if (cpu == TYPE_ADCV2 || cpu == TYPE_ADCV3) {
+		/* Clear ADC interrupt */
+		writel(0, adc->regs + S3C64XX_ADCCLRINT);
+	}
+	return IRQ_HANDLED;
+}
+
+static int s3c_adc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct adc_device *adc;
+	enum s3c_cpu_type cpu = platform_get_device_id(pdev)->driver_data;
+	int ret;
+	unsigned tmp;
+
+	adc = devm_kzalloc(dev, sizeof(*adc), GFP_KERNEL);
+	if (!adc)
+		return -ENOMEM;
+
+	spin_lock_init(&adc->lock);
+
+	adc->pdev = pdev;
+	adc->prescale = S3C2410_ADCCON_PRSCVL(49);
+
+	adc->vdd = devm_regulator_get(dev, "vdd");
+	if (IS_ERR(adc->vdd)) {
+		dev_err(dev, "operating without regulator \"vdd\" .\n");
+		return PTR_ERR(adc->vdd);
+	}
+
+	adc->irq = platform_get_irq(pdev, 1);
+	if (adc->irq <= 0)
+		return -ENOENT;
+
+	ret = devm_request_irq(dev, adc->irq, s3c_adc_irq, 0, dev_name(dev),
+				adc);
+	if (ret < 0) {
+		dev_err(dev, "failed to attach adc irq\n");
+		return ret;
+	}
+
+	adc->clk = devm_clk_get(dev, "adc");
+	if (IS_ERR(adc->clk)) {
+		dev_err(dev, "failed to get adc clock\n");
+		return PTR_ERR(adc->clk);
+	}
+
+	adc->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(adc->regs))
+		return PTR_ERR(adc->regs);
+
+	ret = regulator_enable(adc->vdd);
+	if (ret)
+		return ret;
+
+	clk_prepare_enable(adc->clk);
+
+	tmp = adc->prescale | S3C2410_ADCCON_PRSCEN;
+
+	/* Enable 12-bit ADC resolution */
+	if (cpu == TYPE_ADCV12)
+		tmp |= S3C2416_ADCCON_RESSEL;
+	if (cpu == TYPE_ADCV2 || cpu == TYPE_ADCV3)
+		tmp |= S3C64XX_ADCCON_RESSEL;
+
+	writel(tmp, adc->regs + S3C2410_ADCCON);
+
+	dev_info(dev, "attached adc driver\n");
+
+	platform_set_drvdata(pdev, adc);
+	adc_dev = adc;
+
+	return 0;
+}
+
+static int s3c_adc_remove(struct platform_device *pdev)
+{
+	struct adc_device *adc = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(adc->clk);
+	regulator_disable(adc->vdd);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int s3c_adc_suspend(struct device *dev)
+{
+	struct adc_device *adc = dev_get_drvdata(dev);
+	unsigned long flags;
+	u32 con;
+
+	spin_lock_irqsave(&adc->lock, flags);
+
+	con = readl(adc->regs + S3C2410_ADCCON);
+	con |= S3C2410_ADCCON_STDBM;
+	writel(con, adc->regs + S3C2410_ADCCON);
+
+	disable_irq(adc->irq);
+	spin_unlock_irqrestore(&adc->lock, flags);
+	clk_disable(adc->clk);
+	regulator_disable(adc->vdd);
+
+	return 0;
+}
+
+static int s3c_adc_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct adc_device *adc = platform_get_drvdata(pdev);
+	enum s3c_cpu_type cpu = platform_get_device_id(pdev)->driver_data;
+	int ret;
+	unsigned long tmp;
+
+	ret = regulator_enable(adc->vdd);
+	if (ret)
+		return ret;
+	clk_enable(adc->clk);
+	enable_irq(adc->irq);
+
+	tmp = adc->prescale | S3C2410_ADCCON_PRSCEN;
+
+	/* Enable 12-bit ADC resolution */
+	if (cpu == TYPE_ADCV12)
+		tmp |= S3C2416_ADCCON_RESSEL;
+	if (cpu == TYPE_ADCV2 || cpu == TYPE_ADCV3)
+		tmp |= S3C64XX_ADCCON_RESSEL;
+
+	writel(tmp, adc->regs + S3C2410_ADCCON);
+
+	return 0;
+}
+
+#else
+#define s3c_adc_suspend NULL
+#define s3c_adc_resume NULL
+#endif
+
+static const struct platform_device_id s3c_adc_driver_ids[] = {
+	{
+		.name           = "s3c24xx-adc",
+		.driver_data    = TYPE_ADCV1,
+	}, {
+		.name		= "s3c2443-adc",
+		.driver_data	= TYPE_ADCV11,
+	}, {
+		.name		= "s3c2416-adc",
+		.driver_data	= TYPE_ADCV12,
+	}, {
+		.name           = "s3c64xx-adc",
+		.driver_data    = TYPE_ADCV2,
+	}, {
+		.name		= "samsung-adc-v3",
+		.driver_data	= TYPE_ADCV3,
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, s3c_adc_driver_ids);
+
+static const struct dev_pm_ops adc_pm_ops = {
+	.suspend	= s3c_adc_suspend,
+	.resume		= s3c_adc_resume,
+};
+
+static struct platform_driver s3c_adc_driver = {
+	.id_table	= s3c_adc_driver_ids,
+	.driver		= {
+		.name	= "s3c-adc",
+		.pm	= &adc_pm_ops,
+	},
+	.probe		= s3c_adc_probe,
+	.remove		= s3c_adc_remove,
+};
+
+static int __init adc_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&s3c_adc_driver);
+	if (ret)
+		printk(KERN_ERR "%s: failed to add adc driver\n", __func__);
+
+	return ret;
+}
+
+module_init(adc_init);