[PATCH v3 1/4] serial: 8250_dw: select port setup through platform data

[James Hilliard]

Select feature discovery and DMA attachment through a platform-data setup
callback. The generic callback probes the optional registers and attaches
DMA when a FIFO size is available. Integrations with a fixed configuration
can supply their own setup before the port is registered.

Replace skip_autocfg with the Octeon setup selection. On 64-bit builds,
Octeon continues to skip optional-register probing while retaining its DMA
setup; on 32-bit builds it retains the generic setup. Keep generic setup
for devices without matched platform data as well.

Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/tty/serial/8250/8250_dw.c | 48 +++++++++++++++++++++++++++++++--------
 1 file changed, 38 insertions(+), 10 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index eca02e8bd6d1..9c171c5775a6 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -64,6 +64,7 @@ struct dw8250_platform_data {
 	u8 usr_reg;
 	u32 cpr_value;
 	unsigned int quirks;
+	void (*setup)(struct uart_port *p);
 };
 
 struct dw8250_data {
@@ -76,7 +77,6 @@ struct dw8250_data {
 	struct clk		*pclk;
 	struct reset_control	*rst;
 
-	unsigned int		skip_autocfg:1;
 	unsigned int		uart_16550_compatible:1;
 	unsigned int		in_idle:1;
 
@@ -595,7 +595,6 @@ static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data)
 		p->serial_out = dw8250_serial_outq;
 		p->flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
 		p->type = PORT_OCTEON;
-		data->skip_autocfg = true;
 	}
 #endif
 
@@ -630,6 +629,25 @@ static void dw8250_shutdown(struct uart_port *port)
 	d->no_int_count = 0;
 }
 
+static void dw8250_setup_dma(struct uart_port *p)
+{
+	struct dw8250_data *data = to_dw8250_data(p->private_data);
+	struct uart_8250_port *up = up_to_u8250p(p);
+
+	/* If we have a valid fifosize, try hooking up DMA */
+	if (p->fifosize) {
+		data->data.dma.rxconf.src_maxburst = p->fifosize / 4;
+		data->data.dma.txconf.dst_maxburst = p->fifosize / 4;
+		up->dma = &data->data.dma;
+	}
+}
+
+static void dw8250_setup(struct uart_port *p)
+{
+	dw8250_setup_port(p);
+	dw8250_setup_dma(p);
+}
+
 static int dw8250_probe(struct platform_device *pdev)
 {
 	struct uart_8250_port uart = {}, *up = &uart;
@@ -765,14 +783,11 @@ static int dw8250_probe(struct platform_device *pdev)
 
 	dw8250_setup_dma_filter(p, data);
 
-	if (!data->skip_autocfg)
-		dw8250_setup_port(p);
-
-	/* If we have a valid fifosize, try hooking up DMA */
-	if (p->fifosize) {
-		data->data.dma.rxconf.src_maxburst = p->fifosize / 4;
-		data->data.dma.txconf.dst_maxburst = p->fifosize / 4;
-		up->dma = &data->data.dma;
+	if (data->pdata) {
+		if (data->pdata->setup)
+			data->pdata->setup(p);
+	} else {
+		dw8250_setup(p);
 	}
 
 	data->data.uport = serial8250_register_8250_port(up);
@@ -852,16 +867,23 @@ static _DEFINE_DEV_PM_OPS(dw8250_pm_ops, dw8250_suspend, dw8250_resume,
 
 static const struct dw8250_platform_data dw8250_dw_apb = {
 	.usr_reg = DW_UART_USR,
+	.setup = dw8250_setup,
 };
 
 static const struct dw8250_platform_data dw8250_octeon_3860_data = {
 	.usr_reg = OCTEON_UART_USR,
 	.quirks = DW_UART_QUIRK_OCTEON,
+#ifdef CONFIG_64BIT
+	.setup = dw8250_setup_dma,
+#else
+	.setup = dw8250_setup,
+#endif
 };
 
 static const struct dw8250_platform_data dw8250_armada_38x_data = {
 	.usr_reg = DW_UART_USR,
 	.quirks = DW_UART_QUIRK_ARMADA_38X,
+	.setup = dw8250_setup,
 };
 
 static const struct dw8250_platform_data dw8250_renesas_rzn1_data = {
@@ -876,16 +898,19 @@ static const struct dw8250_platform_data dw8250_renesas_rzn1_data = {
 		     DW_UART_CPR_DMA_EXTRA |
 		     DW_UART_CPR_FIFO_MODE_FROM_SIZE(16),
 	.quirks = DW_UART_QUIRK_CPR_VALUE | DW_UART_QUIRK_IS_DMA_FC,
+	.setup = dw8250_setup,
 };
 
 static const struct dw8250_platform_data dw8250_skip_set_rate_data = {
 	.usr_reg = DW_UART_USR,
 	.quirks = DW_UART_QUIRK_SKIP_SET_RATE,
+	.setup = dw8250_setup,
 };
 
 static const struct dw8250_platform_data dw8250_intc10ee = {
 	.usr_reg = DW_UART_USR,
 	.quirks = DW_UART_QUIRK_IER_KICK,
+	.setup = dw8250_setup,
 };
 
 static const struct dw8250_platform_data dw8250_ultrarisc_dp1000_data = {
@@ -895,11 +920,13 @@ static const struct dw8250_platform_data dw8250_ultrarisc_dp1000_data = {
 		     DW_UART_CPR_DMA_EXTRA |
 		     DW_UART_CPR_FIFO_MODE_FROM_SIZE(32),
 	.quirks = DW_UART_QUIRK_CPR_VALUE,
+	.setup = dw8250_setup,
 };
 
 static const struct dw8250_platform_data dw8250_tda54 = {
 	.usr_reg = DW_UART_USR,
 	.quirks = DW_UART_QUIRK_SKIP_EMPTY_FIFO_READ,
+	.setup = dw8250_setup,
 };
 
 static const struct of_device_id dw8250_of_match[] = {
@@ -918,6 +945,7 @@ MODULE_DEVICE_TABLE(of, dw8250_of_match);
 static const struct dw8250_platform_data dw8250_apmc0d08 = {
 	.usr_reg = DW_UART_USR,
 	.quirks = DW_UART_QUIRK_APMC0D08,
+	.setup = dw8250_setup,
 };
 
 static const struct acpi_device_id dw8250_acpi_match[] = {

-- 
2.53.0