Dear Jiri,
On 2023/5/24 下午 04:34, Jacky Huang wrote:
Dear Jiri,
Thanks for your advice.
On 2023/5/24 下午 03:42, Jiri Slaby wrote:
On 16. 05. 23, 9:52, Jacky Huang wrote:
+static void ma35d1serial_config_port(struct uart_port *port, int
flags)
+{
+ /*
+ * Driver core for serial ports forces a non-zero value for
port type.
+ * Write an arbitrary value here to accommodate the serial core
driver,
+ * as ID part of UAPI is redundant.
+ */
+ port->type = 1;
So this 1 translates to PORT_8250. Why not to use it directly? Or
something more saner like PORT_16550A?
It's not actually 8250 or 16550A.
Can we add the following definition to
'include/uapi/linux/serial_core.h' and use PORT_MA35 instead?
#define PORT_MA35 124
+}
+
+static int ma35d1serial_verify_port(struct uart_port *port, struct
serial_struct *ser)
+{
+ if (port->type != PORT_UNKNOWN && ser->type != 1)
+ return -EINVAL;
+
+ return 0;
+}
...
+static int __init ma35d1serial_console_setup(struct console *co,
char *options)
+{
+ struct device_node *np = ma35d1serial_uart_nodes[co->index];
+ struct uart_ma35d1_port *p = &ma35d1serial_ports[co->index];
+ u32 val32[4];
+ struct uart_port *port;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ /*
+ * Check whether an invalid uart number has been specified, and
You dereferenced ma35d1serial_uart_nodes already. Doesn't
console=ttyNVT1000 (or something like that) crash the system?
I will add the following check before np =
"ma35d1serial_uart_nodes[co->index]".
if (co->index < 0 || co->index >= MA35_UART_NR)
return -EINVAL;
+ * if so, search for the first available port that does have
+ * console support.
The code below doesn't match this comment.
Yes, I will remove the above comment.
+ */
+ if ((co->index < 0) || (co->index >= MA35_UART_NR)) {
+ pr_debug("Console Port%x out of range\n", co->index);
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32_array(np, "reg", val32, 4) != 0)
Shouldn't that 4 be ARRAY_SIZE(val32) instead?
Will be fixed.
+ return -EINVAL;
One \n here please.
Okay, I will add it.
+ p->port.iobase = val32[1];
+ p->port.membase = ioremap(p->port.iobase, MA35_UART_REG_SIZE);
What if this fails?
I will add a check for the return value.
+ p->port.ops = &ma35d1serial_ops;
+ p->port.line = 0;
+ p->port.uartclk = MA35_UART_CONSOLE_CLK;
+
+ port = &ma35d1serial_ports[co->index].port;
Isn't this:
port = &p->port;
?
Either use port on all above lines or drop the "port" variable
completely and use "p->port" below instead.
I will remove port variable and use p->port only.
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+ return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+static struct console ma35d1serial_console = {
+ .name = "ttyNVT",
+ .write = ma35d1serial_console_write,
+ .device = uart_console_device,
+ .setup = ma35d1serial_console_setup,
+ .flags = CON_PRINTBUFFER | CON_ENABLED,
+ .index = -1,
+ .data = &ma35d1serial_reg,
I don't see console->data used anywhere in the driver?
I will remove it.
I removed the " .data = &ma35d1serial_reg", but kernel crashed in
'drivers/tty/serial/serial_core.c'.
The variable 'p' of uart_console_device() refer to a NULL, because
co->data is NULL.
As a result, kernel crashed at 'p->tty_driver'.
struct tty_driver *uart_console_device(struct console *co, int *index)
{
struct uart_driver *p = co->data;
*index = co->index;
return p->tty_driver;
}
We seem to be unable to remove it.
If there are no other considerations, I will keep it in the next version.
+};
...
+static int ma35d1serial_probe(struct platform_device *pdev)
+{
+ struct resource *res_mem;
+ struct uart_ma35d1_port *up;
+ int ret = 0;
+
+ if (pdev->dev.of_node) {
+ ret = of_alias_get_id(pdev->dev.of_node, "serial");
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to get alias/pdev id, errno
%d\n", ret);
+ return ret;
+ }
+ }
+ up = &ma35d1serial_ports[ret];
+ up->port.line = ret;
+ res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res_mem)
+ return -ENODEV;
+
+ up->port.iobase = res_mem->start;
+ up->port.membase = ioremap(up->port.iobase, MA35_UART_REG_SIZE);
Check this too.
Okay, sure.
+ up->port.ops = &ma35d1serial_ops;
+
+ spin_lock_init(&up->port.lock);
+
+ up->clk = of_clk_get(pdev->dev.of_node, 0);
+ if (IS_ERR(up->clk)) {
+ ret = PTR_ERR(up->clk);
+ dev_err(&pdev->dev, "failed to get core clk: %d\n", ret);
+ goto err_iounmap;
+ }
+
+ ret = clk_prepare_enable(up->clk);
+ if (ret)
+ goto err_iounmap;
+
+ if (up->port.line != 0)
+ up->port.uartclk = clk_get_rate(up->clk);
+
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0)
+ goto err_clk_disable;
+
+ up->port.irq = ret;
+ up->port.dev = &pdev->dev;
+ up->port.flags = UPF_BOOT_AUTOCONF;
+
+ platform_set_drvdata(pdev, up);
+
+ ret = uart_add_one_port(&ma35d1serial_reg, &up->port);
+ if (ret < 0)
+ goto err_free_irq;
+
+ return 0;
+
+err_free_irq:
+ free_irq(up->port.irq, &up->port);
+
+err_clk_disable:
+ clk_disable_unprepare(up->clk);
+
+err_iounmap:
+ iounmap(up->port.membase);
+ return ret;
+}
thanks,
Best regards,
Jacky Huang
Best regards,
Jacky Huang
