1 files changed, 108 insertions, 90 deletions

diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index 90953e679e38..2e999cb9c974 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -24,6 +24,7 @@
 #include <linux/slab.h>
 #include <linux/clk.h>
 #include <linux/platform_device.h>
+#include <linux/pm_opp.h>
 #include <linux/delay.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
@@ -160,11 +161,16 @@ enum {
 struct msm_dma {
 	struct dma_chan		*chan;
 	enum dma_data_direction dir;
-	dma_addr_t		phys;
-	unsigned char		*virt;
+	union {
+		struct {
+			dma_addr_t		phys;
+			unsigned char		*virt;
+			unsigned int		count;
+		} rx;
+		struct scatterlist tx_sg;
+	};
 	dma_cookie_t		cookie;
 	u32			enable_bit;
-	unsigned int		count;
 	struct dma_async_tx_descriptor	*desc;
 };
 
@@ -248,8 +254,12 @@ static void msm_stop_dma(struct uart_port *port, struct msm_dma *dma)
 	unsigned int mapped;
 	u32 val;
 
-	mapped = dma->count;
-	dma->count = 0;
+	if (dma->dir == DMA_TO_DEVICE) {
+		mapped = sg_dma_len(&dma->tx_sg);
+	} else {
+		mapped = dma->rx.count;
+		dma->rx.count = 0;
+	}
 
 	dmaengine_terminate_all(dma->chan);
 
@@ -264,8 +274,13 @@ static void msm_stop_dma(struct uart_port *port, struct msm_dma *dma)
 	val &= ~dma->enable_bit;
 	msm_write(port, val, UARTDM_DMEN);
 
-	if (mapped)
-		dma_unmap_single(dev, dma->phys, mapped, dma->dir);
+	if (mapped) {
+		if (dma->dir == DMA_TO_DEVICE) {
+			dma_unmap_sg(dev, &dma->tx_sg, 1, dma->dir);
+			sg_init_table(&dma->tx_sg, 1);
+		} else
+			dma_unmap_single(dev, dma->rx.phys, mapped, dma->dir);
+	}
 }
 
 static void msm_release_dma(struct msm_port *msm_port)
@@ -284,7 +299,7 @@ static void msm_release_dma(struct msm_port *msm_port)
 	if (dma->chan) {
 		msm_stop_dma(&msm_port->uart, dma);
 		dma_release_channel(dma->chan);
-		kfree(dma->virt);
+		kfree(dma->rx.virt);
 	}
 
 	memset(dma, 0, sizeof(*dma));
@@ -356,8 +371,8 @@ static void msm_request_rx_dma(struct msm_port *msm_port, resource_size_t base)
 
 	of_property_read_u32(dev->of_node, "qcom,rx-crci", &crci);
 
-	dma->virt = kzalloc(UARTDM_RX_SIZE, GFP_KERNEL);
-	if (!dma->virt)
+	dma->rx.virt = kzalloc(UARTDM_RX_SIZE, GFP_KERNEL);
+	if (!dma->rx.virt)
 		goto rel_rx;
 
 	memset(&conf, 0, sizeof(conf));
@@ -384,7 +399,7 @@ static void msm_request_rx_dma(struct msm_port *msm_port, resource_size_t base)
 
 	return;
 err:
-	kfree(dma->virt);
+	kfree(dma->rx.virt);
 rel_rx:
 	dma_release_channel(dma->chan);
 no_rx:
@@ -419,7 +434,7 @@ static void msm_start_tx(struct uart_port *port)
 	struct msm_dma *dma = &msm_port->tx_dma;
 
 	/* Already started in DMA mode */
-	if (dma->count)
+	if (sg_dma_len(&dma->tx_sg))
 		return;
 
 	msm_port->imr |= MSM_UART_IMR_TXLEV;
@@ -437,22 +452,22 @@ static void msm_complete_tx_dma(void *args)
 {
 	struct msm_port *msm_port = args;
 	struct uart_port *port = &msm_port->uart;
-	struct circ_buf *xmit = &port->state->xmit;
+	struct tty_port *tport = &port->state->port;
 	struct msm_dma *dma = &msm_port->tx_dma;
 	struct dma_tx_state state;
 	unsigned long flags;
 	unsigned int count;
 	u32 val;
 
-	spin_lock_irqsave(&port->lock, flags);
+	uart_port_lock_irqsave(port, &flags);
 
 	/* Already stopped */
-	if (!dma->count)
+	if (!sg_dma_len(&dma->tx_sg))
 		goto done;
 
 	dmaengine_tx_status(dma->chan, dma->cookie, &state);
 
-	dma_unmap_single(port->dev, dma->phys, dma->count, dma->dir);
+	dma_unmap_sg(port->dev, &dma->tx_sg, 1, dma->dir);
 
 	val = msm_read(port, UARTDM_DMEN);
 	val &= ~dma->enable_bit;
@@ -463,40 +478,42 @@ static void msm_complete_tx_dma(void *args)
 		msm_write(port, MSM_UART_CR_TX_ENABLE, MSM_UART_CR);
 	}
 
-	count = dma->count - state.residue;
+	count = sg_dma_len(&dma->tx_sg) - state.residue;
 	uart_xmit_advance(port, count);
-	dma->count = 0;
+	sg_init_table(&dma->tx_sg, 1);
 
 	/* Restore "Tx FIFO below watermark" interrupt */
 	msm_port->imr |= MSM_UART_IMR_TXLEV;
 	msm_write(port, msm_port->imr, MSM_UART_IMR);
 
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
 		uart_write_wakeup(port);
 
 	msm_handle_tx(port);
 done:
-	spin_unlock_irqrestore(&port->lock, flags);
+	uart_port_unlock_irqrestore(port, flags);
 }
 
 static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count)
 {
-	struct circ_buf *xmit = &msm_port->uart.state->xmit;
 	struct uart_port *port = &msm_port->uart;
+	struct tty_port *tport = &port->state->port;
 	struct msm_dma *dma = &msm_port->tx_dma;
-	void *cpu_addr;
+	unsigned int mapped;
 	int ret;
 	u32 val;
 
-	cpu_addr = &xmit->buf[xmit->tail];
+	sg_init_table(&dma->tx_sg, 1);
+	kfifo_dma_out_prepare(&tport->xmit_fifo, &dma->tx_sg, 1, count);
 
-	dma->phys = dma_map_single(port->dev, cpu_addr, count, dma->dir);
-	ret = dma_mapping_error(port->dev, dma->phys);
-	if (ret)
-		return ret;
+	mapped = dma_map_sg(port->dev, &dma->tx_sg, 1, dma->dir);
+	if (!mapped) {
+		ret = -EIO;
+		goto zero_sg;
+	}
 
-	dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
-						count, DMA_MEM_TO_DEV,
+	dma->desc = dmaengine_prep_slave_sg(dma->chan, &dma->tx_sg, 1,
+						DMA_MEM_TO_DEV,
 						DMA_PREP_INTERRUPT |
 						DMA_PREP_FENCE);
 	if (!dma->desc) {
@@ -519,8 +536,6 @@ static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count)
 	msm_port->imr &= ~MSM_UART_IMR_TXLEV;
 	msm_write(port, msm_port->imr, MSM_UART_IMR);
 
-	dma->count = count;
-
 	val = msm_read(port, UARTDM_DMEN);
 	val |= dma->enable_bit;
 
@@ -535,7 +550,9 @@ static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count)
 	dma_async_issue_pending(dma->chan);
 	return 0;
 unmap:
-	dma_unmap_single(port->dev, dma->phys, count, dma->dir);
+	dma_unmap_sg(port->dev, &dma->tx_sg, 1, dma->dir);
+zero_sg:
+	sg_init_table(&dma->tx_sg, 1);
 	return ret;
 }
 
@@ -549,10 +566,10 @@ static void msm_complete_rx_dma(void *args)
 	unsigned long flags;
 	u32 val;
 
-	spin_lock_irqsave(&port->lock, flags);
+	uart_port_lock_irqsave(port, &flags);
 
 	/* Already stopped */
-	if (!dma->count)
+	if (!dma->rx.count)
 		goto done;
 
 	val = msm_read(port, UARTDM_DMEN);
@@ -569,14 +586,14 @@ static void msm_complete_rx_dma(void *args)
 
 	port->icount.rx += count;
 
-	dma->count = 0;
+	dma->rx.count = 0;
 
-	dma_unmap_single(port->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
+	dma_unmap_single(port->dev, dma->rx.phys, UARTDM_RX_SIZE, dma->dir);
 
 	for (i = 0; i < count; i++) {
 		char flag = TTY_NORMAL;
 
-		if (msm_port->break_detected && dma->virt[i] == 0) {
+		if (msm_port->break_detected && dma->rx.virt[i] == 0) {
 			port->icount.brk++;
 			flag = TTY_BREAK;
 			msm_port->break_detected = false;
@@ -587,16 +604,14 @@ static void msm_complete_rx_dma(void *args)
 		if (!(port->read_status_mask & MSM_UART_SR_RX_BREAK))
 			flag = TTY_NORMAL;
 
-		spin_unlock_irqrestore(&port->lock, flags);
-		sysrq = uart_handle_sysrq_char(port, dma->virt[i]);
-		spin_lock_irqsave(&port->lock, flags);
+		sysrq = uart_prepare_sysrq_char(port, dma->rx.virt[i]);
 		if (!sysrq)
-			tty_insert_flip_char(tport, dma->virt[i], flag);
+			tty_insert_flip_char(tport, dma->rx.virt[i], flag);
 	}
 
 	msm_start_rx_dma(msm_port);
 done:
-	spin_unlock_irqrestore(&port->lock, flags);
+	uart_unlock_and_check_sysrq_irqrestore(port, flags);
 
 	if (count)
 		tty_flip_buffer_push(tport);
@@ -615,13 +630,13 @@ static void msm_start_rx_dma(struct msm_port *msm_port)
 	if (!dma->chan)
 		return;
 
-	dma->phys = dma_map_single(uart->dev, dma->virt,
+	dma->rx.phys = dma_map_single(uart->dev, dma->rx.virt,
 				   UARTDM_RX_SIZE, dma->dir);
-	ret = dma_mapping_error(uart->dev, dma->phys);
+	ret = dma_mapping_error(uart->dev, dma->rx.phys);
 	if (ret)
 		goto sw_mode;
 
-	dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
+	dma->desc = dmaengine_prep_slave_single(dma->chan, dma->rx.phys,
 						UARTDM_RX_SIZE, DMA_DEV_TO_MEM,
 						DMA_PREP_INTERRUPT);
 	if (!dma->desc)
@@ -649,7 +664,7 @@ static void msm_start_rx_dma(struct msm_port *msm_port)
 
 	msm_write(uart, msm_port->imr, MSM_UART_IMR);
 
-	dma->count = UARTDM_RX_SIZE;
+	dma->rx.count = UARTDM_RX_SIZE;
 
 	dma_async_issue_pending(dma->chan);
 
@@ -669,7 +684,7 @@ static void msm_start_rx_dma(struct msm_port *msm_port)
 
 	return;
 unmap:
-	dma_unmap_single(uart->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
+	dma_unmap_single(uart->dev, dma->rx.phys, UARTDM_RX_SIZE, dma->dir);
 
 sw_mode:
 	/*
@@ -762,9 +777,7 @@ static void msm_handle_rx_dm(struct uart_port *port, unsigned int misr)
 			if (!(port->read_status_mask & MSM_UART_SR_RX_BREAK))
 				flag = TTY_NORMAL;
 
-			spin_unlock(&port->lock);
-			sysrq = uart_handle_sysrq_char(port, buf[i]);
-			spin_lock(&port->lock);
+			sysrq = uart_prepare_sysrq_char(port, buf[i]);
 			if (!sysrq)
 				tty_insert_flip_char(tport, buf[i], flag);
 		}
@@ -824,9 +837,7 @@ static void msm_handle_rx(struct uart_port *port)
 		else if (sr & MSM_UART_SR_PAR_FRAME_ERR)
 			flag = TTY_FRAME;
 
-		spin_unlock(&port->lock);
-		sysrq = uart_handle_sysrq_char(port, c);
-		spin_lock(&port->lock);
+		sysrq = uart_prepare_sysrq_char(port, c);
 		if (!sysrq)
 			tty_insert_flip_char(tport, c, flag);
 	}
@@ -836,8 +847,8 @@ static void msm_handle_rx(struct uart_port *port)
 
 static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count)
 {
-	struct circ_buf *xmit = &port->state->xmit;
 	struct msm_port *msm_port = to_msm_port(port);
+	struct tty_port *tport = &port->state->port;
 	unsigned int num_chars;
 	unsigned int tf_pointer = 0;
 	void __iomem *tf;
@@ -851,8 +862,7 @@ static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count)
 		msm_reset_dm_count(port, tx_count);
 
 	while (tf_pointer < tx_count) {
-		int i;
-		char buf[4] = { 0 };
+		unsigned char buf[4] = { 0 };
 
 		if (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY))
 			break;
@@ -863,26 +873,23 @@ static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count)
 		else
 			num_chars = 1;
 
-		for (i = 0; i < num_chars; i++)
-			buf[i] = xmit->buf[xmit->tail + i];
-
+		num_chars = uart_fifo_out(port, buf, num_chars);
 		iowrite32_rep(tf, buf, 1);
-		uart_xmit_advance(port, num_chars);
 		tf_pointer += num_chars;
 	}
 
 	/* disable tx interrupts if nothing more to send */
-	if (uart_circ_empty(xmit))
+	if (kfifo_is_empty(&tport->xmit_fifo))
 		msm_stop_tx(port);
 
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
 		uart_write_wakeup(port);
 }
 
 static void msm_handle_tx(struct uart_port *port)
 {
 	struct msm_port *msm_port = to_msm_port(port);
-	struct circ_buf *xmit = &msm_port->uart.state->xmit;
+	struct tty_port *tport = &port->state->port;
 	struct msm_dma *dma = &msm_port->tx_dma;
 	unsigned int pio_count, dma_count, dma_min;
 	char buf[4] = { 0 };
@@ -906,13 +913,13 @@ static void msm_handle_tx(struct uart_port *port)
 		return;
 	}
 
-	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+	if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) {
 		msm_stop_tx(port);
 		return;
 	}
 
-	pio_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
-	dma_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+	dma_count = pio_count = kfifo_out_linear(&tport->xmit_fifo, NULL,
+			UART_XMIT_SIZE);
 
 	dma_min = 1;	/* Always DMA */
 	if (msm_port->is_uartdm > UARTDM_1P3) {
@@ -947,11 +954,10 @@ static irqreturn_t msm_uart_irq(int irq, void *dev_id)
 	struct uart_port *port = dev_id;
 	struct msm_port *msm_port = to_msm_port(port);
 	struct msm_dma *dma = &msm_port->rx_dma;
-	unsigned long flags;
 	unsigned int misr;
 	u32 val;
 
-	spin_lock_irqsave(&port->lock, flags);
+	uart_port_lock(port);
 	misr = msm_read(port, MSM_UART_MISR);
 	msm_write(port, 0, MSM_UART_IMR); /* disable interrupt */
 
@@ -961,7 +967,7 @@ static irqreturn_t msm_uart_irq(int irq, void *dev_id)
 	}
 
 	if (misr & (MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE)) {
-		if (dma->count) {
+		if (dma->rx.count) {
 			val = MSM_UART_CR_CMD_STALE_EVENT_DISABLE;
 			msm_write(port, val, MSM_UART_CR);
 			val = MSM_UART_CR_CMD_RESET_STALE_INT;
@@ -983,7 +989,7 @@ static irqreturn_t msm_uart_irq(int irq, void *dev_id)
 		msm_handle_delta_cts(port);
 
 	msm_write(port, msm_port->imr, MSM_UART_IMR); /* restore interrupt */
-	spin_unlock_irqrestore(&port->lock, flags);
+	uart_unlock_and_check_sysrq(port);
 
 	return IRQ_HANDLED;
 }
@@ -1096,7 +1102,7 @@ msm_find_best_baud(struct uart_port *port, unsigned int baud,
 
 			if (result == baud)
 				break;
-		} else if (entry->divisor > divisor) {
+		} else {
 			old = target;
 			target = clk_round_rate(msm_port->clk, old + 1);
 			/*
@@ -1128,13 +1134,13 @@ static int msm_set_baud_rate(struct uart_port *port, unsigned int baud,
 	unsigned long flags, rate;
 
 	flags = *saved_flags;
-	spin_unlock_irqrestore(&port->lock, flags);
+	uart_port_unlock_irqrestore(port, flags);
 
 	entry = msm_find_best_baud(port, baud, &rate);
-	clk_set_rate(msm_port->clk, rate);
+	dev_pm_opp_set_rate(port->dev, rate);
 	baud = rate / 16 / entry->divisor;
 
-	spin_lock_irqsave(&port->lock, flags);
+	uart_port_lock_irqsave(port, &flags);
 	*saved_flags = flags;
 	port->uartclk = rate;
 
@@ -1186,6 +1192,7 @@ static void msm_init_clock(struct uart_port *port)
 {
 	struct msm_port *msm_port = to_msm_port(port);
 
+	dev_pm_opp_set_rate(port->dev, port->uartclk);
 	clk_prepare_enable(msm_port->clk);
 	clk_prepare_enable(msm_port->pclk);
 	msm_serial_set_mnd_regs(port);
@@ -1239,6 +1246,7 @@ err_irq:
 
 	clk_disable_unprepare(msm_port->pclk);
 	clk_disable_unprepare(msm_port->clk);
+	dev_pm_opp_set_rate(port->dev, 0);
 
 	return ret;
 }
@@ -1254,6 +1262,7 @@ static void msm_shutdown(struct uart_port *port)
 		msm_release_dma(msm_port);
 
 	clk_disable_unprepare(msm_port->clk);
+	dev_pm_opp_set_rate(port->dev, 0);
 
 	free_irq(port->irq, port);
 }
@@ -1266,7 +1275,7 @@ static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
 	unsigned long flags;
 	unsigned int baud, mr;
 
-	spin_lock_irqsave(&port->lock, flags);
+	uart_port_lock_irqsave(port, &flags);
 
 	if (dma->chan) /* Terminate if any */
 		msm_stop_dma(port, dma);
@@ -1338,7 +1347,7 @@ static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
 	/* Try to use DMA */
 	msm_start_rx_dma(msm_port);
 
-	spin_unlock_irqrestore(&port->lock, flags);
+	uart_port_unlock_irqrestore(port, flags);
 }
 
 static const char *msm_type(struct uart_port *port)
@@ -1419,11 +1428,13 @@ static void msm_power(struct uart_port *port, unsigned int state,
 
 	switch (state) {
 	case 0:
+		dev_pm_opp_set_rate(port->dev, port->uartclk);
 		clk_prepare_enable(msm_port->clk);
 		clk_prepare_enable(msm_port->pclk);
 		break;
 	case 3:
 		clk_disable_unprepare(msm_port->clk);
+		dev_pm_opp_set_rate(port->dev, 0);
 		clk_disable_unprepare(msm_port->pclk);
 		break;
 	default:
@@ -1615,14 +1626,10 @@ static void __msm_console_write(struct uart_port *port, const char *s,
 			num_newlines++;
 	count += num_newlines;
 
-	local_irq_save(flags);
-
-	if (port->sysrq)
-		locked = 0;
-	else if (oops_in_progress)
-		locked = spin_trylock(&port->lock);
+	if (oops_in_progress)
+		locked = uart_port_trylock_irqsave(port, &flags);
 	else
-		spin_lock(&port->lock);
+		uart_port_lock_irqsave(port, &flags);
 
 	if (is_uartdm)
 		msm_reset_dm_count(port, count);
@@ -1661,9 +1668,7 @@ static void __msm_console_write(struct uart_port *port, const char *s,
 	}
 
 	if (locked)
-		spin_unlock(&port->lock);
-
-	local_irq_restore(flags);
+		uart_port_unlock_irqrestore(port, flags);
 }
 
 static void msm_console_write(struct console *co, const char *s,
@@ -1741,6 +1746,12 @@ msm_serial_early_console_setup_dm(struct earlycon_device *device,
 	if (!device->port.membase)
 		return -ENODEV;
 
+	/* Disable DM / single-character modes */
+	msm_write(&device->port, 0, UARTDM_DMEN);
+	msm_write(&device->port, MSM_UART_CR_CMD_RESET_RX, MSM_UART_CR);
+	msm_write(&device->port, MSM_UART_CR_CMD_RESET_TX, MSM_UART_CR);
+	msm_write(&device->port, MSM_UART_CR_TX_ENABLE, MSM_UART_CR);
+
 	device->con->write = msm_serial_early_write_dm;
 	return 0;
 }
@@ -1789,7 +1800,7 @@ static int msm_serial_probe(struct platform_device *pdev)
 	struct resource *resource;
 	struct uart_port *port;
 	const struct of_device_id *id;
-	int irq, line;
+	int irq, line, ret;
 
 	if (pdev->dev.of_node)
 		line = of_alias_get_id(pdev->dev.of_node, "serial");
@@ -1824,6 +1835,15 @@ static int msm_serial_probe(struct platform_device *pdev)
 			return PTR_ERR(msm_port->pclk);
 	}
 
+	ret = devm_pm_opp_set_clkname(&pdev->dev, "core");
+	if (ret)
+		return ret;
+
+	/* OPP table is optional */
+	ret = devm_pm_opp_of_add_table(&pdev->dev);
+	if (ret && ret != -ENODEV)
+		return dev_err_probe(&pdev->dev, ret, "invalid OPP table\n");
+
 	port->uartclk = clk_get_rate(msm_port->clk);
 	dev_info(&pdev->dev, "uartclk = %d\n", port->uartclk);
 
@@ -1843,13 +1863,11 @@ static int msm_serial_probe(struct platform_device *pdev)
 	return uart_add_one_port(&msm_uart_driver, port);
 }
 
-static int msm_serial_remove(struct platform_device *pdev)
+static void msm_serial_remove(struct platform_device *pdev)
 {
 	struct uart_port *port = platform_get_drvdata(pdev);
 
 	uart_remove_one_port(&msm_uart_driver, port);
-
-	return 0;
 }
 
 static const struct of_device_id msm_match_table[] = {