1 files changed, 137 insertions, 0 deletions

diff --git a/arch/arm/plat-mxc/audmux-v2.c b/arch/arm/plat-mxc/audmux-v2.c
index 6f21096086fd..b06954a84436 100644
--- a/arch/arm/plat-mxc/audmux-v2.c
+++ b/arch/arm/plat-mxc/audmux-v2.c
@@ -23,6 +23,7 @@
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/clk.h>
+#include <linux/debugfs.h>
 #include <mach/audmux.h>
 #include <mach/hardware.h>
 
@@ -32,6 +33,140 @@ static void __iomem *audmux_base;
 #define MXC_AUDMUX_V2_PTCR(x)           ((x) * 8)
 #define MXC_AUDMUX_V2_PDCR(x)           ((x) * 8 + 4)
 
+#ifdef CONFIG_DEBUG_FS
+static struct dentry *audmux_debugfs_root;
+
+static int audmux_open_file(struct inode *inode, struct file *file)
+{
+        file->private_data = inode->i_private;
+        return 0;
+}
+
+/* There is an annoying discontinuity in the SSI numbering with regard
+ * to the Linux number of the devices */
+static const char *audmux_port_string(int port)
+{
+        switch (port) {
+        case MX31_AUDMUX_PORT1_SSI0:
+                return "imx-ssi.0";
+        case MX31_AUDMUX_PORT2_SSI1:
+                return "imx-ssi.1";
+        case MX31_AUDMUX_PORT3_SSI_PINS_3:
+                return "SSI3";
+        case MX31_AUDMUX_PORT4_SSI_PINS_4:
+                return "SSI4";
+        case MX31_AUDMUX_PORT5_SSI_PINS_5:
+                return "SSI5";
+        case MX31_AUDMUX_PORT6_SSI_PINS_6:
+                return "SSI6";
+        default:
+                return "UNKNOWN";
+        }
+}
+
+static ssize_t audmux_read_file(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+        ssize_t ret;
+        char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+        int port = (int)file->private_data;
+        u32 pdcr, ptcr;
+
+        if (!buf)
+                return -ENOMEM;
+
+        if (audmux_clk)
+                clk_enable(audmux_clk);
+
+        ptcr = readl(audmux_base + MXC_AUDMUX_V2_PTCR(port));
+        pdcr = readl(audmux_base + MXC_AUDMUX_V2_PDCR(port));
+
+        if (audmux_clk)
+                clk_disable(audmux_clk);
+
+        ret = snprintf(buf, PAGE_SIZE, "PDCR: %08x\nPTCR: %08x\n",
+                       pdcr, ptcr);
+
+        if (ptcr & MXC_AUDMUX_V2_PTCR_TFSDIR)
+                ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                                "TxFS output from %s, ",
+                                audmux_port_string((ptcr >> 27) & 0x7));
+        else
+                ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                                "TxFS input, ");
+
+        if (ptcr & MXC_AUDMUX_V2_PTCR_TCLKDIR)
+                ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                                "TxClk output from %s",
+                                audmux_port_string((ptcr >> 22) & 0x7));
+        else
+                ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                                "TxClk input");
+
+        ret += snprintf(buf + ret, PAGE_SIZE - ret, "\n");
+
+        if (ptcr & MXC_AUDMUX_V2_PTCR_SYN) {
+                ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                                "Port is symmetric");
+        } else {
+                if (ptcr & MXC_AUDMUX_V2_PTCR_RFSDIR)
+                        ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                                        "RxFS output from %s, ",
+                                        audmux_port_string((ptcr >> 17) & 0x7));
+                else
+                        ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                                        "RxFS input, ");
+
+                if (ptcr & MXC_AUDMUX_V2_PTCR_RCLKDIR)
+                        ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                                        "RxClk output from %s",
+                                        audmux_port_string((ptcr >> 12) & 0x7));
+                else
+                        ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                                        "RxClk input");
+        }
+
+        ret += snprintf(buf + ret, PAGE_SIZE - ret,
+                        "\nData received from %s\n",
+                        audmux_port_string((pdcr >> 13) & 0x7));
+
+        ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
+
+        kfree(buf);
+
+        return ret;
+}
+
+static const struct file_operations audmux_debugfs_fops = {
+        .open = audmux_open_file,
+        .read = audmux_read_file,
+};
+
+static void audmux_debugfs_init(void)
+{
+        int i;
+        char buf[20];
+
+        audmux_debugfs_root = debugfs_create_dir("audmux", NULL);
+        if (!audmux_debugfs_root) {
+                pr_warning("Failed to create AUDMUX debugfs root\n");
+                return;
+        }
+
+        for (i = 1; i < 8; i++) {
+                snprintf(buf, sizeof(buf), "ssi%d", i);
+                if (!debugfs_create_file(buf, 0444, audmux_debugfs_root,
+                                         (void *)i, &audmux_debugfs_fops))
+                        pr_warning("Failed to create AUDMUX port %d debugfs file\n",
+                                   i);
+        }
+}
+#else
+static inline void audmux_debugfs_init(void)
+{
+}
+#endif
+
 int mxc_audmux_v2_configure_port(unsigned int port, unsigned int ptcr,
                 unsigned int pdcr)
 {
@@ -68,6 +203,8 @@ static int mxc_audmux_v2_init(void)
         if (cpu_is_mx31() || cpu_is_mx35())
                 audmux_base = IO_ADDRESS(AUDMUX_BASE_ADDR);
 
+        audmux_debugfs_init();
+
         return 0;
 }