serial: sccnxp: Using CLK API for getting UART clock

This patch removes "frequency" parameter from SCCNXP platform_data
and uses CLK API for getting clock. If CLK ommited, default IC
frequency will be used instead.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 22 insertions, 18 deletions

diff --git a/arch/mips/sni/a20r.c b/arch/mips/sni/a20r.c
index dd0ab982d77e..f9407e170476 100644
--- a/arch/mips/sni/a20r.c
+++ b/arch/mips/sni/a20r.c
@@ -122,7 +122,6 @@ static struct resource sc26xx_rsrc[] = {
 
 static struct sccnxp_pdata sccnxp_data = {
         .reg_shift      = 2,
-        .frequency      = 3686400,
         .mctrl_cfg[0]   = MCTRL_SIG(DTR_OP, LINE_OP7) |
                           MCTRL_SIG(RTS_OP, LINE_OP3) |
                           MCTRL_SIG(DSR_IP, LINE_IP5) |
diff --git a/drivers/tty/serial/sccnxp.c b/drivers/tty/serial/sccnxp.c
index 12a5c265f43a..81e70477e6fd 100644
--- a/drivers/tty/serial/sccnxp.c
+++ b/drivers/tty/serial/sccnxp.c
@@ -15,6 +15,7 @@
 #define SUPPORT_SYSRQ
 #endif
 
+#include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/module.h>
 #include <linux/device.h>
@@ -783,9 +784,10 @@ static int sccnxp_probe(struct platform_device *pdev)
         struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         int chiptype = pdev->id_entry->driver_data;
         struct sccnxp_pdata *pdata = dev_get_platdata(&pdev->dev);
-        int i, ret, fifosize, freq_min, freq_max;
+        int i, ret, fifosize, freq_min, freq_max, uartclk;
         struct sccnxp_port *s;
         void __iomem *membase;
+        struct clk *clk;
 
         membase = devm_ioremap_resource(&pdev->dev, res);
         if (IS_ERR(membase))
@@ -898,11 +900,25 @@ static int sccnxp_probe(struct platform_device *pdev)
         } else if (PTR_ERR(s->regulator) == -EPROBE_DEFER)
                 return -EPROBE_DEFER;
 
-        if (!pdata) {
-                dev_warn(&pdev->dev,
-                         "No platform data supplied, using defaults\n");
-                s->pdata.frequency = s->freq_std;
+        clk = devm_clk_get(&pdev->dev, NULL);
+        if (IS_ERR(clk)) {
+                if (PTR_ERR(clk) == -EPROBE_DEFER) {
+                        ret = -EPROBE_DEFER;
+                        goto err_out;
+                }
+                dev_notice(&pdev->dev, "Using default clock frequency\n");
+                uartclk = s->freq_std;
         } else
+                uartclk = clk_get_rate(clk);
+
+        /* Check input frequency */
+        if ((uartclk < freq_min) || (uartclk > freq_max)) {
+                dev_err(&pdev->dev, "Frequency out of bounds\n");
+                ret = -EINVAL;
+                goto err_out;
+        }
+
+        if (pdata)
                 memcpy(&s->pdata, pdata, sizeof(struct sccnxp_pdata));
 
         if (s->pdata.poll_time_us) {
@@ -920,14 +936,6 @@ static int sccnxp_probe(struct platform_device *pdev)
                 }
         }
 
-        /* Check input frequency */
-        if ((s->pdata.frequency < freq_min) ||
-            (s->pdata.frequency > freq_max)) {
-                dev_err(&pdev->dev, "Frequency out of bounds\n");
-                ret = -EINVAL;
-                goto err_out;
-        }
-
         s->uart.owner           = THIS_MODULE;
         s->uart.dev_name        = "ttySC";
         s->uart.major           = SCCNXP_MAJOR;
@@ -959,7 +967,7 @@ static int sccnxp_probe(struct platform_device *pdev)
                 s->port[i].mapbase      = res->start;
                 s->port[i].membase      = membase;
                 s->port[i].regshift     = s->pdata.reg_shift;
-                s->port[i].uartclk      = s->pdata.frequency;
+                s->port[i].uartclk      = uartclk;
                 s->port[i].ops          = &sccnxp_ops;
                 uart_add_one_port(&s->uart, &s->port[i]);
                 /* Set direction to input */
diff --git a/include/linux/platform_data/serial-sccnxp.h b/include/linux/platform_data/serial-sccnxp.h
index bdc510d03245..af0c8c3b89ae 100644
--- a/include/linux/platform_data/serial-sccnxp.h
+++ b/include/linux/platform_data/serial-sccnxp.h
@@ -60,7 +60,6 @@
  * };
  *
  * static struct sccnxp_pdata sc2892_info = {
- *      .frequency      = 3686400,
  *      .mctrl_cfg[0]   = MCTRL_SIG(DIR_OP, LINE_OP0),
  *      .mctrl_cfg[1]   = MCTRL_SIG(DIR_OP, LINE_OP1),
  * };
@@ -78,8 +77,6 @@
 
 /* SCCNXP platform data structure */
 struct sccnxp_pdata {
-        /* Frequency (extrenal clock or crystal) */
-        int                     frequency;
         /* Shift for A0 line */
         const u8                reg_shift;
         /* Modem control lines configuration */