From nobody Mon Sep 17 00:00:00 2001
From: Haavard Skinnemoen <hskinnemoen@atmel.com>
Date: Sun, 14 Jan 2007 19:07:06 +0100
Subject: [ATMEL MCI] Add debugfs support

Export some of the atmel-mci driver state through debugfs. More
specifically:
  * The MCI hardware registers
  * The request currently being processed
  * Pending and processed event masks

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
---
 drivers/mmc/atmel-mci.c |  230 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 230 insertions(+)

Index: linux-2.6.18-avr32/drivers/mmc/atmel-mci.c
===================================================================
--- linux-2.6.18-avr32.orig/drivers/mmc/atmel-mci.c	2007-01-15 15:35:45.000000000 +0100
+++ linux-2.6.18-avr32/drivers/mmc/atmel-mci.c	2007-01-15 15:38:05.000000000 +0100
@@ -79,6 +79,14 @@ struct atmel_mci {
 	struct clk		*mck;
 	struct mmci_platform_data *board;
 	struct platform_device	*pdev;
+
+#ifdef CONFIG_DEBUG_FS
+	struct dentry		*debugfs_root;
+	struct dentry		*debugfs_regs;
+	struct dentry		*debugfs_req;
+	struct dentry		*debugfs_pending_events;
+	struct dentry		*debugfs_completed_events;
+#endif
 };
 
 /* Those printks take an awful lot of time... */
@@ -90,6 +98,224 @@ static unsigned int fmax = 1000000U;
 module_param(fmax, uint, 0444);
 MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
 
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+#define DBG_REQ_BUF_SIZE	(4096 - sizeof(unsigned int))
+
+struct req_dbg_data {
+	unsigned int nbytes;
+	char str[DBG_REQ_BUF_SIZE];
+};
+
+static int req_dbg_open(struct inode *inode, struct file *file)
+{
+	struct atmel_mci *host;
+	struct mmc_request *mrq;
+	struct mmc_command *cmd, *stop;
+	struct mmc_data *data;
+	struct req_dbg_data *priv;
+	char *str;
+	unsigned long n = 0;
+
+	priv = kzalloc(DBG_REQ_BUF_SIZE, GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+	str = priv->str;
+
+	mutex_lock(&inode->i_mutex);
+	host = inode->u.generic_ip;
+
+	spin_lock_irq(&host->mmc->lock);
+	mrq = host->mrq;
+	if (mrq) {
+		cmd = mrq->cmd;
+		data = mrq->data;
+		stop = mrq->stop;
+		n = snprintf(str, DBG_REQ_BUF_SIZE,
+			     "CMD%u(0x%x) %x %x %x %x %x (err %u)\n",
+			     cmd->opcode, cmd->arg, cmd->flags,
+			     cmd->resp[0], cmd->resp[1], cmd->resp[2],
+			     cmd->resp[3], cmd->error);
+		if (n < DBG_REQ_BUF_SIZE && data)
+			n += snprintf(str + n, DBG_REQ_BUF_SIZE - n,
+				      "DATA %u * %u (%u) %x (err %u)\n",
+				      data->blocks, data->blksz,
+				      data->bytes_xfered, data->flags,
+				      data->error);
+		if (n < DBG_REQ_BUF_SIZE && stop)
+			n += snprintf(str + n, DBG_REQ_BUF_SIZE - n,
+				      "CMD%u(0x%x) %x %x %x %x %x (err %u)\n",
+				      stop->opcode, stop->arg, stop->flags,
+				      stop->resp[0], stop->resp[1],
+				      stop->resp[2], stop->resp[3],
+				      stop->error);
+	}
+	spin_unlock_irq(&host->mmc->lock);
+	mutex_unlock(&inode->i_mutex);
+
+	priv->nbytes = min(n, DBG_REQ_BUF_SIZE);
+	file->private_data = priv;
+
+	return 0;
+}
+
+static int req_dbg_read(struct file *file, char __user *buf,
+			size_t nbytes, loff_t *ppos)
+{
+	struct req_dbg_data *priv = file->private_data;
+
+	return simple_read_from_buffer(buf, nbytes, ppos,
+				       priv->str, priv->nbytes);
+}
+
+static int req_dbg_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	return 0;
+}
+
+static const struct file_operations req_dbg_fops = {
+	.owner		= THIS_MODULE,
+	.open		= req_dbg_open,
+	.llseek		= no_llseek,
+	.read		= req_dbg_read,
+	.release	= req_dbg_release,
+};
+
+static int regs_dbg_open(struct inode *inode, struct file *file)
+{
+	struct atmel_mci *host;
+	unsigned int i;
+	u32 *data;
+	int ret = -ENOMEM;
+
+	mutex_lock(&inode->i_mutex);
+	host = inode->u.generic_ip;
+	data = kmalloc(inode->i_size, GFP_KERNEL);
+	if (!data)
+		goto out;
+
+	spin_lock_irq(&host->mmc->lock);
+	for (i = 0; i < inode->i_size / 4; i++)
+		data[i] = __raw_readl(host->regs + i * 4);
+	spin_unlock_irq(&host->mmc->lock);
+
+	file->private_data = data;
+	ret = 0;
+
+out:
+	mutex_unlock(&inode->i_mutex);
+
+	return ret;
+}
+
+static ssize_t regs_dbg_read(struct file *file, char __user *buf,
+			     size_t nbytes, loff_t *ppos)
+{
+	struct inode *inode = file->f_dentry->d_inode;
+	int ret;
+
+	mutex_lock(&inode->i_mutex);
+	ret = simple_read_from_buffer(buf, nbytes, ppos,
+				      file->private_data,
+				      file->f_dentry->d_inode->i_size);
+	mutex_unlock(&inode->i_mutex);
+
+	return ret;
+}
+
+static int regs_dbg_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	return 0;
+}
+
+static const struct file_operations regs_dbg_fops = {
+	.owner		= THIS_MODULE,
+	.open		= regs_dbg_open,
+	.llseek		= generic_file_llseek,
+	.read		= regs_dbg_read,
+	.release	= regs_dbg_release,
+};
+
+static void atmci_init_debugfs(struct atmel_mci *host)
+{
+	struct mmc_host *mmc;
+	struct dentry *root, *regs;
+	struct resource *res;
+
+	mmc = host->mmc;
+	root = debugfs_create_dir(mmc_hostname(mmc), NULL);
+	if (IS_ERR(root) || !root)
+		goto err_root;
+	host->debugfs_root = root;
+
+	regs = debugfs_create_file("regs", 0400, root, host, &regs_dbg_fops);
+	if (!regs)
+		goto err_regs;
+
+	res = platform_get_resource(host->pdev, IORESOURCE_MEM, 0);
+	regs->d_inode->i_size = res->end - res->start + 1;
+	host->debugfs_regs = regs;
+
+	host->debugfs_req = debugfs_create_file("req", 0400, root,
+						host, &req_dbg_fops);
+	if (!host->debugfs_req)
+		goto err_req;
+
+	host->debugfs_pending_events
+		= debugfs_create_u32("pending_events", 0400, root,
+				     (u32 *)&host->pending_events);
+	if (!host->debugfs_pending_events)
+		goto err_pending_events;
+
+	host->debugfs_completed_events
+		= debugfs_create_u32("completed_events", 0400, root,
+				     (u32 *)&host->completed_events);
+	if (!host->debugfs_completed_events)
+		goto err_completed_events;
+
+	return;
+
+err_completed_events:
+	debugfs_remove(host->debugfs_pending_events);
+err_pending_events:
+	debugfs_remove(host->debugfs_req);
+err_req:
+	debugfs_remove(host->debugfs_regs);
+err_regs:
+	debugfs_remove(host->debugfs_root);
+err_root:
+	host->debugfs_root = NULL;
+	dev_err(&host->pdev->dev,
+		"failed to initialize debugfs for %s\n",
+		mmc_hostname(mmc));
+}
+
+static void atmci_cleanup_debugfs(struct atmel_mci *host)
+{
+	if (host->debugfs_root) {
+		debugfs_remove(host->debugfs_completed_events);
+		debugfs_remove(host->debugfs_pending_events);
+		debugfs_remove(host->debugfs_req);
+		debugfs_remove(host->debugfs_regs);
+		debugfs_remove(host->debugfs_root);
+		host->debugfs_root = NULL;
+	}
+}
+#else
+static inline void atmci_init_debugfs(struct atmel_mci *host)
+{
+
+}
+
+static inline void atmci_cleanup_debugfs(struct atmel_mci *host)
+{
+
+}
+#endif /* CONFIG_DEBUG_FS */
+
 static inline unsigned int ns_to_clocks(struct atmel_mci *host,
 					unsigned int ns)
 {
@@ -709,6 +935,8 @@ static int __devinit atmci_probe(struct 
 	printk(KERN_INFO "%s: Atmel MCI controller at 0x%08lx irq %d\n",
 	       mmc_hostname(mmc), host->mapbase, irq);
 
+	atmci_init_debugfs(host);
+
 	return 0;
 
 out_free_irq:
@@ -734,6 +962,8 @@ static int __devexit atmci_remove(struct
 	platform_set_drvdata(pdev, NULL);
 
 	if (host) {
+		atmci_cleanup_debugfs(host);
+
 		mmc_remove_host(host->mmc);
 
 		mci_writel(host, IDR, ~0UL);