serial: max3100: Get crystal frequency via device property

Get crystal frequency via device property instead of using
a platform data.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240409144721.638326-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c
index 4a4343e7b1fa1fb15340a007e35d6b3d67394dd8..446bc78061e3cc71bc315d24be0f0d39aae8d1bc 100644 (file)
--- a/drivers/tty/serial/max3100.c
+++ b/drivers/tty/serial/max3100.c
@@ -20,6 +20,7 @@
 #include <linux/slab.h>
 #include <linux/device.h>
 #include <linux/module.h>
+#include <linux/property.h>
 #include <linux/serial_core.h>
 #include <linux/serial.h>
 #include <linux/spi/spi.h>
@@ -30,17 +31,6 @@
 
 #include <asm/unaligned.h>
 
-/**
- * struct plat_max3100 - MAX3100 SPI UART platform data
- * @crystal:             1 for 3.6864 Mhz, 0 for 1.8432
- *
- * You should use this structure in your machine description to specify
- * how the MAX3100 is connected.
- */
-struct plat_max3100 {
-       int crystal;
-};
-
 #define MAX3100_C    (1<<14)
 #define MAX3100_D    (0<<14)
 #define MAX3100_W    (1<<15)
@@ -106,7 +96,6 @@ struct max3100_port {
        int irq;                /* irq assigned to the max3100 */
 
        int minor;              /* minor number */
-       int crystal;            /* 1 if 3.6864Mhz crystal 0 for 1.8432 */
        int loopback_commit;    /* need to change loopback */
        int loopback;           /* 1 if we are in loopback mode */
 
@@ -426,7 +415,8 @@ max3100_set_termios(struct uart_port *port, struct ktermios *termios,
        struct max3100_port *s = container_of(port,
                                              struct max3100_port,
                                              port);
-       int baud = 0;
+       unsigned int baud = port->uartclk / 16;
+       unsigned int baud230400 = (baud == 230400) ? 1 : 0;
        unsigned cflag;
        u32 param_new, param_mask, parity = 0;
 
@@ -439,40 +429,40 @@ max3100_set_termios(struct uart_port *port, struct ktermios *termios,
        param_new = s->conf & MAX3100_BAUD;
        switch (baud) {
        case 300:
-               if (s->crystal)
+               if (baud230400)
                        baud = s->baud;
                else
                        param_new = 15;
                break;
        case 600:
-               param_new = 14 + s->crystal;
+               param_new = 14 + baud230400;
                break;
        case 1200:
-               param_new = 13 + s->crystal;
+               param_new = 13 + baud230400;
                break;
        case 2400:
-               param_new = 12 + s->crystal;
+               param_new = 12 + baud230400;
                break;
        case 4800:
-               param_new = 11 + s->crystal;
+               param_new = 11 + baud230400;
                break;
        case 9600:
-               param_new = 10 + s->crystal;
+               param_new = 10 + baud230400;
                break;
        case 19200:
-               param_new = 9 + s->crystal;
+               param_new = 9 + baud230400;
                break;
        case 38400:
-               param_new = 8 + s->crystal;
+               param_new = 8 + baud230400;
                break;
        case 57600:
-               param_new = 1 + s->crystal;
+               param_new = 1 + baud230400;
                break;
        case 115200:
-               param_new = 0 + s->crystal;
+               param_new = 0 + baud230400;
                break;
        case 230400:
-               if (s->crystal)
+               if (baud230400)
                        param_new = 0;
                else
                        baud = s->baud;
@@ -575,7 +565,7 @@ static int max3100_startup(struct uart_port *port)
        dev_dbg(&s->spi->dev, "%s\n", __func__);
 
        s->conf = MAX3100_RM;
-       s->baud = s->crystal ? 230400 : 115200;
+       s->baud = port->uartclk / 16;
        s->rx_enabled = 1;
 
        if (s->suspending)
@@ -718,8 +708,8 @@ static int uart_driver_registered;
 
 static int max3100_probe(struct spi_device *spi)
 {
+       struct device *dev = &spi->dev;
        int i, retval;
-       struct plat_max3100 *pdata;
        u16 rx;
 
        mutex_lock(&max3100s_lock);
@@ -755,20 +745,21 @@ static int max3100_probe(struct spi_device *spi)
        max3100s[i]->irq = spi->irq;
        spin_lock_init(&max3100s[i]->conf_lock);
        spi_set_drvdata(spi, max3100s[i]);
-       pdata = dev_get_platdata(&spi->dev);
-       max3100s[i]->crystal = pdata->crystal;
        max3100s[i]->minor = i;
        timer_setup(&max3100s[i]->timer, max3100_timeout, 0);
 
        dev_dbg(&spi->dev, "%s: adding port %d\n", __func__, i);
        max3100s[i]->port.irq = max3100s[i]->irq;
-       max3100s[i]->port.uartclk = max3100s[i]->crystal ? 3686400 : 1843200;
        max3100s[i]->port.fifosize = 16;
        max3100s[i]->port.ops = &max3100_ops;
        max3100s[i]->port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
        max3100s[i]->port.line = i;
        max3100s[i]->port.type = PORT_MAX3100;
        max3100s[i]->port.dev = &spi->dev;
+
+       /* Read clock frequency from a property, uart_add_one_port() will fail if it's not set */
+       device_property_read_u32(dev, "clock-frequency", &max3100s[i]->port.uartclk);
+
        retval = uart_add_one_port(&max3100_uart_driver, &max3100s[i]->port);
        if (retval < 0)
                dev_warn(&spi->dev,