tty: serial: qcom-geni-serial: refactor qcom_geni_serial_send_chunk_fifo()

Shuffle the code a bit, drop unneeded variables, make types of others
more consistent and use uart_xmit_advance() instead of handling
tail->xmit manually.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20221229155030.418800-11-brgl@bgdev.pl
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 bd91a6a..3705c0f 100644 (file)
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -93,7 +93,7 @@
 #define IO_MACRO_IO2_IO3_SWAP          0x4640
 
 /* We always configure 4 bytes per FIFO word */
-#define BYTES_PER_FIFO_WORD            4
+#define BYTES_PER_FIFO_WORD            4U
 
 struct qcom_geni_private_data {
        /* NOTE: earlycon port will have NULL here */
@@ -704,36 +704,28 @@ static void qcom_geni_serial_start_rx(struct uart_port *uport)
        writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
 }
 
-static int qcom_geni_serial_send_chunk_fifo(struct uart_port *uport,
-                                           unsigned int chunk)
+static void qcom_geni_serial_send_chunk_fifo(struct uart_port *uport,
+                                            unsigned int chunk)
 {
        struct qcom_geni_serial_port *port = to_dev_port(uport);
        struct circ_buf *xmit = &uport->state->xmit;
-       size_t remaining = chunk;
-       int i, tail = xmit->tail;
-
-       for (i = 0; i < chunk; ) {
-               unsigned int tx_bytes;
-               u8 buf[sizeof(u32)];
-               int c;
+       unsigned int tx_bytes, c, remaining = chunk;
+       u8 buf[BYTES_PER_FIFO_WORD];
 
+       while (remaining) {
                memset(buf, 0, sizeof(buf));
-               tx_bytes = min_t(size_t, remaining, BYTES_PER_FIFO_WORD);
+               tx_bytes = min(remaining, BYTES_PER_FIFO_WORD);
 
                for (c = 0; c < tx_bytes ; c++) {
-                       buf[c] = xmit->buf[tail++];
-                       tail &= UART_XMIT_SIZE - 1;
+                       buf[c] = xmit->buf[xmit->tail];
+                       uart_xmit_advance(uport, 1);
                }
 
                iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
 
-               i += tx_bytes;
-               uport->icount.tx += tx_bytes;
                remaining -= tx_bytes;
                port->tx_remaining -= tx_bytes;
        }
-
-       return tail;
 }
 
 static void qcom_geni_serial_handle_tx(struct uart_port *uport, bool done,
@@ -778,7 +770,7 @@ static void qcom_geni_serial_handle_tx(struct uart_port *uport, bool done,
                                        uport->membase + SE_GENI_M_IRQ_EN);
        }
 
-       xmit->tail = qcom_geni_serial_send_chunk_fifo(uport, chunk);
+       qcom_geni_serial_send_chunk_fifo(uport, chunk);
 
        /*
         * The tx fifo watermark is level triggered and latched. Though we had