Re: [PATCH v7 2/2] tty/serial: Add Spreadtrum sc9836-uart driver support

From: Lyra Zhang
Date: Fri Jan 23 2015 - 08:39:18 EST


On Fri, Jan 23, 2015 at 9:31 PM, Peter Hurley <peter@xxxxxxxxxxxxxxxxxx> wrote:
> Hi Chunyan,
>
> Just the minor fix to zeroing the stack local in sprd_set_termios()
> and using dev_get_drvdata() in sprd_suspend()/sprd_resume().
>

ok, I see.

> Regards,
> Peter Hurley
>
> On 01/23/2015 08:01 AM, 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.
>
> [...]
>
>> +static void sprd_set_termios(struct uart_port *port,
>> + struct ktermios *termios,
>> + struct ktermios *old)
>> +{
>> + unsigned int baud, quot;
>> + unsigned int lcr, fc;
>
> unsigned int lcr = 0, fc;
>
>> + unsigned long flags;
>> +
>> + /* ask the core to calculate the divisor for us */
>> + baud = uart_get_baud_rate(port, termios, old, 0, SPRD_BAUD_IO_LIMIT);
>> +
>> + quot = (unsigned int)((port->uartclk + baud / 2) / baud);
>> +
>> + /* set data length */
>> + switch (termios->c_cflag & CSIZE) {
>> + case CS5:
>> + lcr |= SPRD_LCR_DATA_LEN5;
>> + break;
>> + case CS6:
>> + lcr |= SPRD_LCR_DATA_LEN6;
>> + break;
>> + case CS7:
>> + lcr |= SPRD_LCR_DATA_LEN7;
>> + break;
>> + case CS8:
>> + default:
>> + lcr |= SPRD_LCR_DATA_LEN8;
>> + break;
>> + }
>> +
>> + /* calculate stop bits */
>> + lcr &= ~(SPRD_LCR_STOP_1BIT | SPRD_LCR_STOP_2BIT);
>> + if (termios->c_cflag & CSTOPB)
>> + lcr |= SPRD_LCR_STOP_2BIT;
>> + else
>> + lcr |= SPRD_LCR_STOP_1BIT;
>> +
>> + /* calculate parity */
>> + lcr &= ~SPRD_LCR_PARITY;
>> + termios->c_cflag &= ~CMSPAR; /* no support mark/space */
>> + if (termios->c_cflag & PARENB) {
>> + lcr |= SPRD_LCR_PARITY_EN;
>> + if (termios->c_cflag & PARODD)
>> + lcr |= SPRD_LCR_ODD_PAR;
>> + else
>> + lcr |= SPRD_LCR_EVEN_PAR;
>> + }
>
> [...]
>
>> +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;
>> +
>> + pdev->id = index;
>
> see my recent reply regarding this and sprd_suspend/sprd_resume.
>
>> +
>> + 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;
>> + }
>> + up->mapbase = res->start;
>> + up->membase = devm_ioremap_resource(&pdev->dev, res);
>> + if (IS_ERR(up->membase))
>> + return PTR_ERR(up->membase);
>> +
>> + irq = platform_get_irq(pdev, 0);
>> + if (irq < 0) {
>> + dev_err(&pdev->dev, "not provide irq resource\n");
>> + return -ENODEV;
>> + }
>> + up->irq = irq;
>> +
>> + if (!sprd_ports_num) {
>> + ret = uart_register_driver(&sprd_uart_driver);
>> + if (ret < 0) {
>> + pr_err("Failed to register SPRD-UART driver\n");
>> + return ret;
>> + }
>> + }
>> + sprd_ports_num++;
>> +
>> + ret = uart_add_one_port(&sprd_uart_driver, up);
>> + if (ret) {
>> + sprd_port[index] = NULL;
>> + sprd_remove(pdev);
>> + }
>> +
>> + platform_set_drvdata(pdev, up);
>> +
>> + return ret;
>> +}
>> +
>> +static int sprd_suspend(struct device *dev)
>> +{
>> + int id = to_platform_device(dev)->id;
>> + struct uart_port *port = &sprd_port[id]->port;
>> +
>> + uart_suspend_port(&sprd_uart_driver, port);
>
> same comment: see my recent reply using dev_get_drvdata().
>

ok, i see. thanks!

Chunyan

>> +
>> + return 0;
>> +}
>> +
>> +static int sprd_resume(struct device *dev)
>> +{
>> + int id = to_platform_device(dev)->id;
>> + struct uart_port *port = &sprd_port[id]->port;
>> +
>> + uart_resume_port(&sprd_uart_driver, port);
>> +
>> + return 0;
>> +}
>> +
>
>
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