tty: serial: qcom_geni_serial: Move loopback support to TIOCM_LOOP

Remove code from the driver that create and maintain loopback sysfs node.
Instead use the ioctl TIOCMSET with TIOCM_LOOP argument to set HW to
loopback mode.

Signed-off-by: Akash Asthana <akashast@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1578321905-25843-3-git-send-email-akashast@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 1e164839662cec52959df3d4ea6ba39522221dcc..191abb18fc2a7e9208f69c1896c03106b716c270 100644 (file)
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -89,7 +89,11 @@
 #define DEF_TX_WM              2
 #define DEF_FIFO_WIDTH_BITS    32
 #define UART_RX_WM             2
-#define MAX_LOOPBACK_CFG       3
+
+/* SE_UART_LOOPBACK_CFG */
+#define RX_TX_SORTED   BIT(0)
+#define CTS_RTS_SORTED BIT(1)
+#define RX_TX_CTS_RTS_SORTED   (RX_TX_SORTED | CTS_RTS_SORTED)
 
 #ifdef CONFIG_CONSOLE_POLL
 #define CONSOLE_RX_BYTES_PW 1
@@ -161,30 +165,6 @@ static struct qcom_geni_serial_port qcom_geni_uart_ports[GENI_UART_PORTS] = {
        },
 };
 
-static ssize_t loopback_show(struct device *dev,
-                               struct device_attribute *attr, char *buf)
-{
-       struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
-
-       return snprintf(buf, sizeof(u32), "%d\n", port->loopback);
-}
-
-static ssize_t loopback_store(struct device *dev,
-                               struct device_attribute *attr, const char *buf,
-                               size_t size)
-{
-       struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
-       u32 loopback;
-
-       if (kstrtoint(buf, 0, &loopback) || loopback > MAX_LOOPBACK_CFG) {
-               dev_err(dev, "Invalid input\n");
-               return -EINVAL;
-       }
-       port->loopback = loopback;
-       return size;
-}
-static DEVICE_ATTR_RW(loopback);
-
 static struct qcom_geni_serial_port qcom_geni_console_port = {
        .uport = {
                .iotype = UPIO_MEM,
@@ -234,10 +214,14 @@ static void qcom_geni_serial_set_mctrl(struct uart_port *uport,
                                                        unsigned int mctrl)
 {
        u32 uart_manual_rfr = 0;
+       struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
 
        if (uart_console(uport))
                return;
 
+       if (mctrl & TIOCM_LOOP)
+               port->loopback = RX_TX_CTS_RTS_SORTED;
+
        if (!(mctrl & TIOCM_RTS))
                uart_manual_rfr = UART_MANUAL_RFR_EN | UART_RFR_NOT_READY;
        writel(uart_manual_rfr, uport->membase + SE_UART_MANUAL_RFR);
@@ -1308,8 +1292,6 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
        uport->private_data = drv;
        platform_set_drvdata(pdev, port);
        port->handle_rx = console ? handle_rx_console : handle_rx_uart;
-       if (!console)
-               device_create_file(uport->dev, &dev_attr_loopback);
 
        ret = uart_add_one_port(drv, uport);
        if (ret)