serial: sccnxp: Allow to use non-standard baud rates (efa0f494) · Commits · 戴 / test

drivers/tty/serial/sccnxp.c

+19 −3

Original line number	Diff line number	Diff line
		@@ -48,7 +48,6 @@
		# define MR2_STOP1 (7 << 0)
		# define MR2_STOP2 (0xf << 0)
		#define SCCNXP_SR_REG (0x01)
		#define SCCNXP_CSR_REG SCCNXP_SR_REG
		# define SR_RXRDY (1 << 0)
		# define SR_FULL (1 << 1)
		# define SR_TXRDY (1 << 2)
		@@ -57,6 +56,8 @@
		# define SR_PE (1 << 5)
		# define SR_FE (1 << 6)
		# define SR_BRK (1 << 7)
		#define SCCNXP_CSR_REG (SCCNXP_SR_REG)
		# define CSR_TIMER_MODE (0x0d)
		#define SCCNXP_CR_REG (0x02)
		# define CR_RX_ENABLE (1 << 0)
		# define CR_RX_DISABLE (1 << 1)
		@@ -83,9 +84,12 @@
		# define IMR_RXRDY (1 << 1)
		# define ISR_TXRDY(x) (1 << ((x * 4) + 0))
		# define ISR_RXRDY(x) (1 << ((x * 4) + 1))
		#define SCCNXP_CTPU_REG (0x06)
		#define SCCNXP_CTPL_REG (0x07)
		#define SCCNXP_IPR_REG (0x0d)
		#define SCCNXP_OPCR_REG SCCNXP_IPR_REG
		#define SCCNXP_SOP_REG (0x0e)
		#define SCCNXP_START_COUNTER_REG SCCNXP_SOP_REG
		#define SCCNXP_ROP_REG (0x0f)

		/* Route helpers */
		@@ -255,7 +259,7 @@ static int sccnxp_update_best_err(int a, int b, int *besterr)
		{
		int err = abs(a - b);

		if ((besterr < 0) \|\| (besterr > err)) {
		if (*besterr > err) {
		*besterr = err;
		return 0;
		}
		@@ -303,10 +307,22 @@ static const struct {
		static int sccnxp_set_baud(struct uart_port *port, int baud)
		{
		struct sccnxp_port *s = dev_get_drvdata(port->dev);
		int div_std, tmp_baud, bestbaud = baud, besterr = -1;
		int div_std, tmp_baud, bestbaud = INT_MAX, besterr = INT_MAX;
		struct sccnxp_chip *chip = s->chip;
		u8 i, acr = 0, csr = 0, mr0 = 0;

		/* Find divisor to load to the timer preset registers */
		div_std = DIV_ROUND_CLOSEST(port->uartclk, 2 * 16 * baud);
		if ((div_std >= 2) && (div_std <= 0xffff)) {
		bestbaud = DIV_ROUND_CLOSEST(port->uartclk, 2 * 16 * div_std);
		sccnxp_update_best_err(baud, bestbaud, &besterr);
		csr = CSR_TIMER_MODE;
		sccnxp_port_write(port, SCCNXP_CTPU_REG, div_std >> 8);
		sccnxp_port_write(port, SCCNXP_CTPL_REG, div_std);
		/* Issue start timer/counter command */
		sccnxp_port_read(port, SCCNXP_START_COUNTER_REG);
		}

		/* Find best baud from table */
		for (i = 0; baud_std[i].baud && besterr; i++) {
		if (baud_std[i].mr0 && !(chip->flags & SCCNXP_HAVE_MR0))

Admin message