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authorGuanbing Huang <albanhuang@tencent.com>2024-04-16 11:16:59 +0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2024-04-17 13:14:30 +0200
commit64c79dfbc45863821e172a606f453b39c8a8be6b (patch)
treed4a48e0336c765201baebb935c43d95388ea16a3 /drivers/tty
parent18ba7f2d99f698251294fe9521da3f00d03f96aa (diff)
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serial: 8250_pnp: Support configurable reg shift property
The 16550a serial port based on the ACPI table requires obtaining the reg-shift attribute. In the ACPI scenario, If the reg-shift property is not configured like in DTS, the 16550a serial driver cannot read or write controller registers properly during initialization. Signed-off-by: Guanbing Huang <albanhuang@tencent.com> Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Bing Fan <tombinfan@tencent.com> Tested-by: Linheng Du <dylanlhdu@tencent.com> Link: https://lore.kernel.org/r/4726ecea8f7bfbfe42501b4f6ad9fe5b38994574.1713234515.git.albanhuang@tencent.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
-rw-r--r--drivers/tty/serial/8250/8250_pnp.c40
1 files changed, 25 insertions, 15 deletions
diff --git a/drivers/tty/serial/8250/8250_pnp.c b/drivers/tty/serial/8250/8250_pnp.c
index 1974bbadc975..8f72a7de1d1d 100644
--- a/drivers/tty/serial/8250/8250_pnp.c
+++ b/drivers/tty/serial/8250/8250_pnp.c
@@ -435,6 +435,7 @@ serial_pnp_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
{
struct uart_8250_port uart, *port;
int ret, line, flags = dev_id->driver_data;
+ unsigned char iotype;
if (flags & UNKNOWN_DEV) {
ret = serial_pnp_guess_board(dev);
@@ -443,37 +444,46 @@ serial_pnp_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
}
memset(&uart, 0, sizeof(uart));
- if (pnp_irq_valid(dev, 0))
- uart.port.irq = pnp_irq(dev, 0);
if ((flags & CIR_PORT) && pnp_port_valid(dev, 2)) {
uart.port.iobase = pnp_port_start(dev, 2);
- uart.port.iotype = UPIO_PORT;
+ iotype = UPIO_PORT;
} else if (pnp_port_valid(dev, 0)) {
uart.port.iobase = pnp_port_start(dev, 0);
- uart.port.iotype = UPIO_PORT;
+ iotype = UPIO_PORT;
} else if (pnp_mem_valid(dev, 0)) {
uart.port.mapbase = pnp_mem_start(dev, 0);
- uart.port.iotype = UPIO_MEM;
+ uart.port.mapsize = pnp_mem_len(dev, 0);
+ iotype = UPIO_MEM;
uart.port.flags = UPF_IOREMAP;
} else
return -ENODEV;
- dev_dbg(&dev->dev,
- "Setup PNP port: port %#lx, mem %#llx, irq %u, type %u\n",
- uart.port.iobase, (unsigned long long)uart.port.mapbase,
- uart.port.irq, uart.port.iotype);
+ uart.port.uartclk = 1843200;
+ uart.port.dev = &dev->dev;
+ uart.port.flags |= UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
+
+ ret = uart_read_port_properties(&uart.port);
+ /* no interrupt -> fall back to polling */
+ if (ret == -ENXIO)
+ ret = 0;
+ if (ret)
+ return ret;
+
+ /*
+ * The previous call may not set iotype correctly when reg-io-width
+ * property is absent and it doesn't support IO port resource.
+ */
+ uart.port.iotype = iotype;
if (flags & CIR_PORT) {
uart.port.flags |= UPF_FIXED_PORT | UPF_FIXED_TYPE;
uart.port.type = PORT_8250_CIR;
}
- uart.port.flags |= UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
- if (pnp_irq_flags(dev, 0) & IORESOURCE_IRQ_SHAREABLE)
- uart.port.flags |= UPF_SHARE_IRQ;
- uart.port.uartclk = 1843200;
- device_property_read_u32(&dev->dev, "clock-frequency", &uart.port.uartclk);
- uart.port.dev = &dev->dev;
+ dev_dbg(&dev->dev,
+ "Setup PNP port: port %#lx, mem %#llx, size %#llx, irq %u, type %u\n",
+ uart.port.iobase, (unsigned long long)uart.port.mapbase,
+ (unsigned long long)uart.port.mapsize, uart.port.irq, uart.port.iotype);
line = serial8250_register_8250_port(&uart);
if (line < 0 || (flags & CIR_PORT))