serial: 8250: dw: Create a generic platform data structure

Use device tree match data rather than multiple calls to
of_device_is_compatible() by introducing a platform data structure and
adding a quirks mask.

Provide a stub to the compatibles without quirks to simplify the
handling of the upcoming changes.
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
[<miquel.raynal@bootlin.com: Minor changes + creation of a real pdata structure]
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-3-miquel.raynal@bootlin.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/8250/8250_dw.c

@@ -19,6 +19,7 @@
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/workqueue.h>
 #include <linux/notifier.h>
 #include <linux/slab.h>
@@ -37,6 +38,11 @@
 /* DesignWare specific register fields */
 #define DW_UART_MCR_SIRE		BIT(6)
 
+/* Quirks */
+#define DW_UART_QUIRK_OCTEON		BIT(0)
+#define DW_UART_QUIRK_ARMADA_38X	BIT(1)
+#define DW_UART_QUIRK_SKIP_SET_RATE	BIT(2)
+
 static inline struct dw8250_data *clk_to_dw8250_data(struct notifier_block *nb)
 {
 	return container_of(nb, struct dw8250_data, clk_notifier);
@@ -366,6 +372,7 @@ static bool dw8250_idma_filter(struct dma_chan *chan, void *param)
 static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data)
 {
 	struct device_node *np = p->dev->of_node;
+	unsigned int quirks = data->pdata->quirks;
 
 	if (np) {
 		int id;
@@ -375,7 +382,7 @@ static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data)
 		if (id >= 0)
 			p->line = id;
 #ifdef CONFIG_64BIT
-		if (of_device_is_compatible(np, "cavium,octeon-3860-uart")) {
+		if (quirks & DW_UART_QUIRK_OCTEON) {
 			p->serial_in = dw8250_serial_inq;
 			p->serial_out = dw8250_serial_outq;
 			p->flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
@@ -391,9 +398,9 @@ static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data)
 			p->serial_out = dw8250_serial_out32be;
 		}
 
-		if (of_device_is_compatible(np, "marvell,armada-38x-uart"))
+		if (quirks & DW_UART_QUIRK_ARMADA_38X)
 			p->serial_out = dw8250_serial_out38x;
-		if (of_device_is_compatible(np, "starfive,jh7100-uart"))
+		if (quirks & DW_UART_QUIRK_SKIP_SET_RATE)
 			p->set_termios = dw8250_do_set_termios;
 
 	} else if (acpi_dev_present("APMC0D08", NULL, -1)) {
@@ -456,6 +463,7 @@ static int dw8250_probe(struct platform_device *pdev)
 
 	data->data.dma.fn = dw8250_fallback_dma_filter;
 	data->usr_reg = DW_UART_USR;
+	data->pdata = device_get_match_data(p->dev);
 	p->private_data = &data->data;
 
 	data->uart_16550_compatible = device_property_read_bool(dev,
@@ -672,12 +680,30 @@ static const struct dev_pm_ops dw8250_pm_ops = {
 	SET_RUNTIME_PM_OPS(dw8250_runtime_suspend, dw8250_runtime_resume, NULL)
 };
 
+static const struct dw8250_platform_data dw8250_dw_apb = {
+};
+
+static const struct dw8250_platform_data dw8250_octeon_3860_data = {
+	.quirks = DW_UART_QUIRK_OCTEON,
+};
+
+static const struct dw8250_platform_data dw8250_armada_38x_data = {
+	.quirks = DW_UART_QUIRK_ARMADA_38X,
+};
+
+static const struct dw8250_platform_data dw8250_renesas_rzn1_data = {
+};
+
+static const struct dw8250_platform_data dw8250_starfive_jh7100_data = {
+	.quirks = DW_UART_QUIRK_SKIP_SET_RATE,
+};
+
 static const struct of_device_id dw8250_of_match[] = {
-	{ .compatible = "snps,dw-apb-uart" },
-	{ .compatible = "cavium,octeon-3860-uart" },
-	{ .compatible = "marvell,armada-38x-uart" },
-	{ .compatible = "renesas,rzn1-uart" },
-	{ .compatible = "starfive,jh7100-uart" },
+	{ .compatible = "snps,dw-apb-uart", .data = &dw8250_dw_apb },
+	{ .compatible = "cavium,octeon-3860-uart", .data = &dw8250_octeon_3860_data },
+	{ .compatible = "marvell,armada-38x-uart", .data = &dw8250_armada_38x_data },
+	{ .compatible = "renesas,rzn1-uart", .data = &dw8250_renesas_rzn1_data },
+	{ .compatible = "starfive,jh7100-uart", .data = &dw8250_starfive_jh7100_data },
 	{ /* Sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, dw8250_of_match);

drivers/tty/serial/8250/8250_dwlib.h

@@ -21,8 +21,13 @@ struct dw8250_port_data {
 	u8			dlf_size;
 };
 
+struct dw8250_platform_data {
+	unsigned int quirks;
+};
+
 struct dw8250_data {
 	struct dw8250_port_data	data;
+	const struct dw8250_platform_data *pdata;
 
 	u8			usr_reg;
 	int			msr_mask_on;