Hi,

On Wednesday 28 January 2015 04:38 PM, Chunyan Zhang wrote:

Add a full sc9836-uart driver for SC9836 SoC which is based on the
spreadtrum sharkl64 platform.
This driver also support earlycon.

Originally-by: Lanqing Liu [off-list ref]
Signed-off-by: Orson Zhai <redacted>
Signed-off-by: Chunyan Zhang <redacted>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Peter Hurley <redacted>
---
  drivers/tty/serial/Kconfig       |   18 +
  drivers/tty/serial/Makefile      |    1 +
  drivers/tty/serial/sprd_serial.c |  793 ++++++++++++++++++++++++++++++++++++++
  include/uapi/linux/serial_core.h |    3 +
  4 files changed, 815 insertions(+)
  create mode 100644 drivers/tty/serial/sprd_serial.c

(...)

+static int sprd_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct uart_port *up;
+	struct clk *clk;
+	int irq;
+	int index;
+	int ret;
+
+	for (index = 0; index < ARRAY_SIZE(sprd_port); index++)
+		if (sprd_port[index] == NULL)
+			break;
+
+	if (index == ARRAY_SIZE(sprd_port))
+		return -EBUSY;
+
+	index = sprd_probe_dt_alias(index, &pdev->dev);
+
+	sprd_port[index] = devm_kzalloc(&pdev->dev,
+		sizeof(*sprd_port[index]), GFP_KERNEL);
+	if (!sprd_port[index])
+		return -ENOMEM;
+
+	up = &sprd_port[index]->port;
+	up->dev = &pdev->dev;
+	up->line = index;
+	up->type = PORT_SPRD;
+	up->iotype = SERIAL_IO_PORT;
+	up->uartclk = SPRD_DEF_RATE;
+	up->fifosize = SPRD_FIFO_SIZE;
+	up->ops = &serial_sprd_ops;
+	up->flags = UPF_BOOT_AUTOCONF;
+
+	clk = devm_clk_get(&pdev->dev, NULL);
+	if (!IS_ERR(clk))
+		up->uartclk = clk_get_rate(clk);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "not provide mem resource\n");
+		return -ENODEV;
+	}

This check is not required. It will be done by devm_ioremap_resource()

+	up->mapbase = res->start;
+	up->membase = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(up->membase))
+		return PTR_ERR(up->membase);
+

-- 
Thanks,
Varka Bhadram.