[PATCH v1 05/14] serial: 8250_bcm2835aux: Switch to use uart_read_port_properties()

Andy Shevchenko
2024-02-21T18:35:04Z

Since we have now a common helper to read port properties
use it instead of sparse home grown solution.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/tty/serial/8250/8250_bcm2835aux.c | 92 +++++++++++------------
1 file changed, 42 insertions(+), 50 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index beac6b340ace..69c3c5ca77f7 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -45,10 +45,6 @@ struct bcm2835aux_data {
u32 cntl;
};

-struct bcm2835_aux_serial_driver_data {
- resource_size_t offset;
-};
-
static void bcm2835aux_rs485_start_tx(struct uart_8250_port *up)
{
if (!(up->port.rs485.flags & SER_RS485_RX_DURING_TX)) {
@@ -85,10 +81,9 @@ static void bcm2835aux_rs485_stop_tx(struct uart_8250_port *up)

static int bcm2835aux_serial_probe(struct platform_device *pdev)
{
- const struct bcm2835_aux_serial_driver_data *bcm_data;
+ const struct software_node *bcm2835_swnode;
struct uart_8250_port up = { };
struct bcm2835aux_data *data;
- resource_size_t offset = 0;
struct resource *res;
unsigned int uartclk;
int ret;
@@ -101,12 +96,8 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
/* initialize data */
up.capabilities = UART_CAP_FIFO | UART_CAP_MINI;
up.port.dev = &pdev->dev;
- up.port.regshift = 2;
up.port.type = PORT_16550;
- up.port.iotype = UPIO_MEM;
- up.port.fifosize = 8;
- up.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT | UPF_FIXED_TYPE |
- UPF_SKIP_TEST | UPF_IOREMAP;
+ up.port.flags = UPF_FIXED_PORT | UPF_FIXED_TYPE | UPF_SKIP_TEST | UPF_IOREMAP;
up.port.rs485_config = serial8250_em485_config;
up.port.rs485_supported = serial8250_em485_supported;
up.rs485_start_tx = bcm2835aux_rs485_start_tx;
@@ -122,12 +113,6 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
if (IS_ERR(data->clk))
return dev_err_probe(&pdev->dev, PTR_ERR(data->clk), "could not get clk\n");

- /* get the interrupt */
- ret = platform_get_irq(pdev, 0);
- if (ret < 0)
- return ret;
- up.port.irq = ret;
-
/* map the main registers */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
@@ -135,52 +120,40 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
return -EINVAL;
}

- bcm_data = device_get_match_data(&pdev->dev);
+ up.port.mapbase = res->start;
+ up.port.mapsize = resource_size(res);

- /* Some UEFI implementations (e.g. tianocore/edk2 for the Raspberry Pi)
- * describe the miniuart with a base address that encompasses the auxiliary
- * registers shared between the miniuart and spi.
- *
- * This is due to historical reasons, see discussion here :
- * https://edk2.groups.io/g/devel/topic/87501357#84349
- *
- * We need to add the offset between the miniuart and auxiliary
- * registers to get the real miniuart base address.
- */
- if (bcm_data)
- offset = bcm_data->offset;
+ bcm2835_swnode = device_get_match_data(&pdev->dev);
+ if (bcm2835_swnode) {
+ ret = device_add_software_node(&pdev->dev, bcm2835_swnode);
+ if (ret)
+ return ret;
+ }

- up.port.mapbase = res->start + offset;
- up.port.mapsize = resource_size(res) - offset;
+ ret = uart_read_port_properties(&up.port, true);
+ if (ret)
+ goto rm_swnode;

- /* Check for a fixed line number */
- ret = of_alias_get_id(pdev->dev.of_node, "serial");
- if (ret >= 0)
- up.port.line = ret;
+ up.port.regshift = 2;
+ up.port.fifosize = 8;

/* enable the clock as a last step */
ret = clk_prepare_enable(data->clk);
if (ret) {
- dev_err(&pdev->dev, "unable to enable uart clock - %d\n",
- ret);
- return ret;
+ dev_err_probe(&pdev->dev, ret, "unable to enable uart clock\n");
+ goto rm_swnode;
}

uartclk = clk_get_rate(data->clk);
- if (!uartclk) {
- ret = device_property_read_u32(&pdev->dev, "clock-frequency", &uartclk);
- if (ret) {
- dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
- goto dis_clk;
- }
- }
+ if (uartclk)
+ up.port.uartclk = uartclk;

/* the HW-clock divider for bcm2835aux is 8,
* but 8250 expects a divider of 16,
* so we have to multiply the actual clock by 2
* to get identical baudrates.
*/
- up.port.uartclk = uartclk * 2;
+ up.port.uartclk *= 2;

/* register the port */
ret = serial8250_register_8250_port(&up);
@@ -194,6 +167,8 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)

dis_clk:
clk_disable_unprepare(data->clk);
+rm_swnode:
+ device_remove_software_node(&pdev->dev);
return ret;
}

@@ -203,10 +178,27 @@ static void bcm2835aux_serial_remove(struct platform_device *pdev)

serial8250_unregister_port(data->line);
clk_disable_unprepare(data->clk);
+ device_remove_software_node(&pdev->dev);
}

-static const struct bcm2835_aux_serial_driver_data bcm2835_acpi_data = {
- .offset = 0x40,
+/*
+ * Some UEFI implementations (e.g. tianocore/edk2 for the Raspberry Pi)
+ * describe the miniuart with a base address that encompasses the auxiliary
+ * registers shared between the miniuart and spi.
+ *
+ * This is due to historical reasons, see discussion here:
+ * https://edk2.groups.io/g/devel/topic/87501357#84349
+ *
+ * We need to add the offset between the miniuart and auxiliary registers
+ * to get the real miniuart base address.
+ */
+static const struct property_entry bcm2835_acpi_properties[] = {
+ PROPERTY_ENTRY_U32("reg-offset", 0x40),
+ { }
+};
+
+static const struct software_node bcm2835_acpi_node = {
+ .properties = bcm2835_acpi_properties,
};

static const struct of_device_id bcm2835aux_serial_match[] = {
@@ -216,7 +208,7 @@ static const struct of_device_id bcm2835aux_serial_match[] = {
MODULE_DEVICE_TABLE(of, bcm2835aux_serial_match);

static const struct acpi_device_id bcm2835aux_serial_acpi_match[] = {
- { "BCM2836", (kernel_ulong_t)&bcm2835_acpi_data },
+ { "BCM2836", (kernel_ulong_t)&bcm2835_acpi_node },
{ }
};
MODULE_DEVICE_TABLE(acpi, bcm2835aux_serial_acpi_match);
--
2.43.0.rc1.1.gbec44491f096