[PATCH 2/2] i2c-exynos5: add debugfs support for registers

Naveen Krishna Chatradhi
2012-12-25T11:26:52Z

This patch replaces the dev_vdbg with debugfs function calls
in i2c-exynos5.c driver.

Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
---
Changes since v1:
The debugfs implementation is a suggestion by Felipe Balbi.
Its not tested, Implemented only for review purpose..

drivers/i2c/busses/i2c-exynos5.c | 140 +++++++++++++++++++++++++++++---------
1 file changed, 109 insertions(+), 31 deletions(-)

diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c
index 7614f60..2d2da22 100644
--- a/drivers/i2c/busses/i2c-exynos5.c
+++ b/drivers/i2c/busses/i2c-exynos5.c
@@ -12,6 +12,7 @@

#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/debugfs.h>

#include <linux/i2c.h>
#include <linux/init.h>
@@ -55,6 +56,7 @@ struct exynos5_i2c {

int bus_num;
int speed_mode;
+ struct dentry *debugfs_root;
};

static const struct of_device_id exynos5_i2c_match[] = {
@@ -63,39 +65,112 @@ static const struct of_device_id exynos5_i2c_match[] = {
};
MODULE_DEVICE_TABLE(of, exynos5_i2c_match);

-/* TODO: Should go to debugfs */
-static inline void dump_i2c_register(struct exynos5_i2c *i2c)
+static int exynos5_i2c_regs_show(struct seq_file *s, void *data)
{
- dev_vdbg(i2c->dev, "Register dump(%d) :\n %x\n %x\n %x\n %x\n"
- " %x\n %x\n %x\n %x\n %x\n"
- " %x\n %x\n %x\n %x\n %x\n"
- " %x\n %x\n %x\n %x\n %x\n"
- " %x\n %x\n %x\n %x\n %x\n",
- i2c->suspended,
- readl(i2c->regs + HSI2C_CTL),
- readl(i2c->regs + HSI2C_FIFO_CTL),
- readl(i2c->regs + HSI2C_TRAILIG_CTL),
- readl(i2c->regs + HSI2C_CLK_CTL),
- readl(i2c->regs + HSI2C_CLK_SLOT),
- readl(i2c->regs + HSI2C_INT_ENABLE),
- readl(i2c->regs + HSI2C_INT_STATUS),
- readl(i2c->regs + HSI2C_ERR_STATUS),
- readl(i2c->regs + HSI2C_FIFO_STATUS),
- readl(i2c->regs + HSI2C_TX_DATA),
- readl(i2c->regs + HSI2C_RX_DATA),
- readl(i2c->regs + HSI2C_CONF),
- readl(i2c->regs + HSI2C_AUTO_CONF),
- readl(i2c->regs + HSI2C_TIMEOUT),
- readl(i2c->regs + HSI2C_MANUAL_CMD),
- readl(i2c->regs + HSI2C_TRANS_STATUS),
- readl(i2c->regs + HSI2C_TIMING_HS1),
- readl(i2c->regs + HSI2C_TIMING_HS2),
- readl(i2c->regs + HSI2C_TIMING_HS3),
- readl(i2c->regs + HSI2C_TIMING_FS1),
- readl(i2c->regs + HSI2C_TIMING_FS2),
- readl(i2c->regs + HSI2C_TIMING_FS3),
- readl(i2c->regs + HSI2C_TIMING_SLA),
+ struct exynos5_i2c *i2c = (struct exynos5_i2c *)s->private;
+
+ if (i2c->suspended) {
+ seq_printf(s, "i2c suspended, can't read registers\n");
+ return 0;
+ }
+
+ pm_runtime_get_sync(i2c->dev);
+
+ seq_printf(s, "CTL:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_CTL));
+ seq_printf(s, "FIFO_CTL:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_FIFO_CTL));
+ seq_printf(s, "TRAILIG_CTL:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TRAILIG_CTL));
+ seq_printf(s, "CLK_CTL:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_CLK_CTL));
+ seq_printf(s, "CLK_SLOT:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_CLK_SLOT));
+ seq_printf(s, "INT_ENABLE:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_INT_ENABLE));
+ seq_printf(s, "INT_STATUS:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_INT_STATUS));
+ seq_printf(s, "FIFO_STATUS:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_FIFO_STATUS));
+ seq_printf(s, "TX_DATA:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TX_DATA));
+ seq_printf(s, "RX_DATA:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_RX_DATA));
+ seq_printf(s, "CONF:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_CONF));
+ seq_printf(s, "AUTO_CONF:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_AUTO_CONF));
+ seq_printf(s, "TIMEOUT:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TIMEOUT));
+ seq_printf(s, "MANUAL_CMD:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_MANUAL_CMD));
+ seq_printf(s, "TRANS_STATUS:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TRANS_STATUS));
+ seq_printf(s, "TIMING_HS1:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TIMING_HS1));
+ seq_printf(s, "TIMING_HS2:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TIMING_HS2));
+ seq_printf(s, "TIMING_HS3:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TIMING_HS3));
+ seq_printf(s, "TIMING_FS1:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TIMING_FS1));
+ seq_printf(s, "TIMING_FS2:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TIMING_FS2));
+ seq_printf(s, "TIMING_FS3:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TIMING_FS3));
+ seq_printf(s, "TIMING_SLA:\t\t0x%08x\n",
+ readl(i2c->regs + HSI2C_TIMING_SLA));
+ seq_printf(s, "ADDR:\t\t0x%08x\n",
readl(i2c->regs + HSI2C_ADDR));
+
+ pm_runtime_mark_last_busy(i2c->dev);
+ pm_runtime_put_autosuspend(i2c->dev);
+
+ return 0;
+}
+
+static int exynos5_i2c_regs_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, exynos5_i2c_regs_show, inode->i_private);
+}
+
+static const struct file_operations exynos5_i2c_regs_fops = {
+ .open = exynos5_i2c_regs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void exynos5_i2c_debugfs(struct exynos5_i2c *i2c)
+{
+ if (i2c->debugfs_root)
+ debugfs_create_file("regs", S_IRUSR, i2c->debugfs_root,
+ i2c, &exynos5_i2c_regs_fops);
+}
+
+static void exynos5_i2c_add_debugfs(struct exynos5_i2c *i2c)
+{
+ struct dentry *root;
+
+ root = debugfs_create_dir(dev_name(i2c->dev), NULL);
+ if (IS_ERR(root))
+ /* Don't complain -- debugfs just isn't enabled */
+ return;
+ if (!root)
+ /* Complain -- debugfs is enabled, but it failed to
+ * create the directory. */
+ goto err_root;
+
+ i2c->debugfs_root = root;
+ return;
+
+ err_root:
+ dev_err(i2c->dev, "failed to initialize debugfs\n");
+}
+
+void exynos5_i2c_remove_debugfs(struct exynos5_i2c *i2c)
+{
+ debugfs_remove_recursive(i2c->debugfs_root);
}

static inline void exynos5_i2c_stop(struct exynos5_i2c *i2c, int ret)
@@ -553,6 +628,8 @@ static int exynos5_i2c_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "%s: Exynos5 HS-I2C adapter\n",
dev_name(&i2c->adap.dev));

+ exynos5_i2c_add_debugfs(i2c);
+ exynos5_i2c_debugfs(i2c);
clk_disable_unprepare(i2c->clk);
pm_runtime_mark_last_busy(i2c->dev);
pm_runtime_put_autosuspend(i2c->dev);
@@ -586,6 +663,7 @@ static int exynos5_i2c_remove(struct platform_device *pdev)

iounmap(i2c->regs);
platform_set_drvdata(pdev, NULL);
+ exynos5_i2c_remove_debugfs(i2c);

return 0;
}
--
1.7.9.5