regulators/db8500: split off shared dbx500 code

As we progress with DB5500 and future voltage domain regulators
based on very similar hardware as found in the DB8500 PRCMU,
it makes sense to split off the generic parts and introduce
some generic debug code for the DBx500 regulators. This patch
accoplish a basic abstraction of the DBx500 voltage domain
regulators.

Signed-off-by: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 241 insertions, 0 deletions

diff --git a/drivers/regulator/dbx500-prcmu.c b/drivers/regulator/dbx500-prcmu.c
new file mode 100644
index 000000000000..f2e5ecdc5864
--- /dev/null
+++ b/drivers/regulator/dbx500-prcmu.c
@@ -0,0 +1,241 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * License Terms: GNU General Public License v2
+ * Authors: Sundar Iyer <sundar.iyer@stericsson.com> for ST-Ericsson
+ *          Bengt Jonsson <bengt.g.jonsson@stericsson.com> for ST-Ericsson
+ *
+ * UX500 common part of Power domain regulators
+ */
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/regulator/driver.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+
+#include "dbx500-prcmu.h"
+
+/*
+ * power state reference count
+ */
+static int power_state_active_cnt; /* will initialize to zero */
+static DEFINE_SPINLOCK(power_state_active_lock);
+
+int power_state_active_get(void)
+{
+	unsigned long flags;
+	int cnt;
+
+	spin_lock_irqsave(&power_state_active_lock, flags);
+	cnt = power_state_active_cnt;
+	spin_unlock_irqrestore(&power_state_active_lock, flags);
+
+	return cnt;
+}
+
+void power_state_active_enable(void)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&power_state_active_lock, flags);
+	power_state_active_cnt++;
+	spin_unlock_irqrestore(&power_state_active_lock, flags);
+}
+
+int power_state_active_disable(void)
+{
+	int ret = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&power_state_active_lock, flags);
+	if (power_state_active_cnt <= 0) {
+		pr_err("power state: unbalanced enable/disable calls\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	power_state_active_cnt--;
+out:
+	spin_unlock_irqrestore(&power_state_active_lock, flags);
+	return ret;
+}
+
+#ifdef CONFIG_REGULATOR_DEBUG
+
+static struct ux500_regulator_debug {
+	struct dentry *dir;
+	struct dentry *status_file;
+	struct dentry *power_state_cnt_file;
+	struct dbx500_regulator_info *regulator_array;
+	int num_regulators;
+	u8 *state_before_suspend;
+	u8 *state_after_suspend;
+} rdebug;
+
+void ux500_regulator_suspend_debug(void)
+{
+	int i;
+	for (i = 0; i < rdebug.num_regulators; i++)
+		rdebug.state_before_suspend[i] =
+			rdebug.regulator_array[i].is_enabled;
+}
+
+void ux500_regulator_resume_debug(void)
+{
+	int i;
+	for (i = 0; i < rdebug.num_regulators; i++)
+		rdebug.state_after_suspend[i] =
+			rdebug.regulator_array[i].is_enabled;
+}
+
+static int ux500_regulator_power_state_cnt_print(struct seq_file *s, void *p)
+{
+	struct device *dev = s->private;
+	int err;
+
+	/* print power state count */
+	err = seq_printf(s, "ux500-regulator power state count: %i\n",
+		power_state_active_get());
+	if (err < 0)
+		dev_err(dev, "seq_printf overflow\n");
+
+	return 0;
+}
+
+static int ux500_regulator_power_state_cnt_open(struct inode *inode,
+	struct file *file)
+{
+	return single_open(file, ux500_regulator_power_state_cnt_print,
+		inode->i_private);
+}
+
+static const struct file_operations ux500_regulator_power_state_cnt_fops = {
+	.open = ux500_regulator_power_state_cnt_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+	.owner = THIS_MODULE,
+};
+
+static int ux500_regulator_status_print(struct seq_file *s, void *p)
+{
+	struct device *dev = s->private;
+	int err;
+	int i;
+
+	/* print dump header */
+	err = seq_printf(s, "ux500-regulator status:\n");
+	if (err < 0)
+		dev_err(dev, "seq_printf overflow\n");
+
+	err = seq_printf(s, "%31s : %8s : %8s\n", "current",
+		"before", "after");
+	if (err < 0)
+		dev_err(dev, "seq_printf overflow\n");
+
+	for (i = 0; i < rdebug.num_regulators; i++) {
+		struct dbx500_regulator_info *info;
+		/* Access per-regulator data */
+		info = &rdebug.regulator_array[i];
+
+		/* print status */
+		err = seq_printf(s, "%20s : %8s : %8s : %8s\n", info->desc.name,
+			info->is_enabled ? "enabled" : "disabled",
+			rdebug.state_before_suspend[i] ? "enabled" : "disabled",
+			rdebug.state_after_suspend[i] ? "enabled" : "disabled");
+		if (err < 0)
+			dev_err(dev, "seq_printf overflow\n");
+	}
+
+	return 0;
+}
+
+static int ux500_regulator_status_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, ux500_regulator_status_print,
+		inode->i_private);
+}
+
+static const struct file_operations ux500_regulator_status_fops = {
+	.open = ux500_regulator_status_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+	.owner = THIS_MODULE,
+};
+
+int __attribute__((weak)) dbx500_regulator_testcase(
+	struct dbx500_regulator_info *regulator_info,
+	int num_regulators)
+{
+	return 0;
+}
+
+int __devinit
+ux500_regulator_debug_init(struct platform_device *pdev,
+	struct dbx500_regulator_info *regulator_info,
+	int num_regulators)
+{
+	/* create directory */
+	rdebug.dir = debugfs_create_dir("ux500-regulator", NULL);
+	if (!rdebug.dir)
+		goto exit_no_debugfs;
+
+	/* create "status" file */
+	rdebug.status_file = debugfs_create_file("status",
+		S_IRUGO, rdebug.dir, &pdev->dev,
+		&ux500_regulator_status_fops);
+	if (!rdebug.status_file)
+		goto exit_destroy_dir;
+
+	/* create "power-state-count" file */
+	rdebug.power_state_cnt_file = debugfs_create_file("power-state-count",
+		S_IRUGO, rdebug.dir, &pdev->dev,
+		&ux500_regulator_power_state_cnt_fops);
+	if (!rdebug.power_state_cnt_file)
+		goto exit_destroy_status;
+
+	rdebug.regulator_array = regulator_info;
+	rdebug.num_regulators = num_regulators;
+
+	rdebug.state_before_suspend = kzalloc(num_regulators, GFP_KERNEL);
+	if (!rdebug.state_before_suspend) {
+		dev_err(&pdev->dev,
+			"could not allocate memory for saving state\n");
+		goto exit_destroy_power_state;
+	}
+
+	rdebug.state_after_suspend = kzalloc(num_regulators, GFP_KERNEL);
+	if (!rdebug.state_after_suspend) {
+		dev_err(&pdev->dev,
+			"could not allocate memory for saving state\n");
+		goto exit_free;
+	}
+
+	dbx500_regulator_testcase(regulator_info, num_regulators);
+	return 0;
+
+exit_free:
+	kfree(rdebug.state_before_suspend);
+exit_destroy_power_state:
+	debugfs_remove(rdebug.power_state_cnt_file);
+exit_destroy_status:
+	debugfs_remove(rdebug.status_file);
+exit_destroy_dir:
+	debugfs_remove(rdebug.dir);
+exit_no_debugfs:
+	dev_err(&pdev->dev, "failed to create debugfs entries.\n");
+	return -ENOMEM;
+}
+
+int __devexit ux500_regulator_debug_exit(void)
+{
+	debugfs_remove_recursive(rdebug.dir);
+	kfree(rdebug.state_after_suspend);
+	kfree(rdebug.state_before_suspend);
+
+	return 0;
+}
+#endif