// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/arch/arm/mach-omap1/serial.c
*
* OMAP1 serial support.
*/
#include <linux/gpio/machine.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/serial.h>
#include <linux/tty.h>
#include <linux/serial_8250.h>
#include <linux/serial_reg.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <asm/mach-types.h>
#include "common.h"
#include "serial.h"
#include "mux.h"
#include "pm.h"
#include "soc.h"
static struct clk * uart1_ck;
static struct clk * uart2_ck;
static struct clk * uart3_ck;
static inline unsigned int omap_serial_in(struct plat_serial8250_port *up,
int offset)
{
offset <<= up->regshift;
return (unsigned int)__raw_readb(up->membase + offset);
}
static inline void omap_serial_outp(struct plat_serial8250_port *p, int offset,
int value)
{
offset <<= p->regshift;
__raw_writeb(value, p->membase + offset);
}
/*
* Internal UARTs need to be initialized for the 8250 autoconfig to work
* properly. Note that the TX watermark initialization may not be needed
* once the 8250.c watermark handling code is merged.
*/
static void __init omap_serial_reset(struct plat_serial8250_port *p)
{
omap_serial_outp(p, UART_OMAP_MDR1,
UART_OMAP_MDR1_DISABLE); /* disable UART */
omap_serial_outp(p, UART_OMAP_SCR, 0x08); /* TX watermark */
omap_serial_outp(p, UART_OMAP_MDR1,
UART_OMAP_MDR1_16X_MODE); /* enable UART */
if (!cpu_is_omap15xx()) {
omap_serial_outp(p, UART_OMAP_SYSC, 0x01);
while (!(omap_serial_in(p, UART_OMAP_SYSC) & 0x01));
}
}
static struct plat_serial8250_port serial_platform_data[] = {
{
.mapbase = OMAP1_UART1_BASE,
.irq = INT_UART1,
.flags = UPF_BOOT_AUTOCONF,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = OMAP16XX_BASE_BAUD * 16,
},
{
.mapbase = OMAP1_UART2_BASE,
.irq = INT_UART2,
.flags = UPF_BOOT_AUTOCONF,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = OMAP16XX_BASE_BAUD * 16,
},
{
.mapbase = OMAP1_UART3_BASE,
.irq = INT_UART3,
.flags = UPF_BOOT_AUTOCONF,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = OMAP16XX_BASE_BAUD * 16,
},
{ },
};
static struct platform_device serial_device = {
.name = "serial8250",
.id = PLAT8250_DEV_PLATFORM,
.dev = {
.platform_data = serial_platform_data,
},
};
/*
* Note that on Innovator-1510 UART2 pins conflict with USB2.
* By default UART2 does not work on Innovator-1510 if you have
* USB OHCI enabled. To use UART2, you must disable USB2 first.
*/
void __init omap_serial_init(void)
{
int i;
if (cpu_is_omap15xx()) {
serial_platform_data[0].uartclk = OMAP1510_BASE_BAUD * 16;
serial_platform_data[1].uartclk = OMAP1510_BASE_BAUD * 16;
serial_platform_data[2].uartclk = OMAP1510_BASE_BAUD * 16;
}
for (i = 0; i < ARRAY_SIZE(serial_platform_data) - 1; i++) {
/* Static mapping, never released */
serial_platform_data[i].membase =
ioremap(serial_platform_data[i].mapbase, SZ_2K);
if (!serial_platform_data[i].membase) {
printk(KERN_ERR "Could not ioremap uart%i\n", i);
continue;
}
switch (i) {
case 0:
uart1_ck = clk_get(NULL, "uart1_ck");
if (IS_ERR(uart1_ck))
printk("Could not get uart1_ck\n");
else {
clk_prepare_enable(uart1_ck);
if (cpu_is_omap15xx())
clk_set_rate(uart1_ck, 12000000);
}
break;
case 1:
uart2_ck = clk_get(NULL, "uart2_ck");
if (IS_ERR(uart2_ck))
printk("Could not get uart2_ck\n");
else {
clk_prepare_enable(uart2_ck);
if (cpu_is_omap15xx())
clk_set_rate(uart2_ck, 12000000);
else
clk_set_rate(uart2_ck, 48000000);
}
break;
case 2:
uart3_ck = clk_get(NULL, "uart3_ck");
if (IS_ERR(uart3_ck))
printk("Could not get uart3_ck\n");
else {
clk_prepare_enable(uart3_ck);
if (cpu_is_omap15xx())
clk_set_rate(uart3_ck, 12000000);
}
break;
}
omap_serial_reset(&serial_platform_data[i]);
}
}
#ifdef CONFIG_OMAP_SERIAL_WAKE
static irqreturn_t omap_serial_wake_interrupt(int irq, void *dev_id)
{
/* Need to do something with serial port right after wake-up? */
return IRQ_HANDLED;
}
/*
* Reroutes serial RX lines to GPIO lines for the duration of
* sleep to allow waking up the device from serial port even
* in deep sleep.
*/
void omap_serial_wake_trigger(int enable)
{
if (!cpu_is_omap16xx())
return;
if (uart1_ck != NULL) {
if (enable)
omap_cfg_reg(V14_16XX_GPIO37);
else
omap_cfg_reg(V14_16XX_UART1_RX);
}
if (uart2_ck != NULL) {
if (enable)
omap_cfg_reg(R9_16XX_GPIO18);
else
omap_cfg_reg(R9_16XX_UART2_RX);
}
if (uart3_ck != NULL) {
if (enable)
omap_cfg_reg(L14_16XX_GPIO49);
else
omap_cfg_reg(L14_16XX_UART3_RX);
}
}
static void __init omap_serial_set_port_wakeup(int idx)
{
struct gpio_desc *d;
int ret;
d = gpiod_get_index(NULL, "wakeup", idx, GPIOD_IN);
if (IS_ERR(d)) {
pr_err("Unable to get UART wakeup GPIO descriptor\n");
return;
}
ret = request_irq(gpiod_to_irq(d), &omap_serial_wake_interrupt,
IRQF_TRIGGER_RISING, "serial wakeup", NULL);
if (ret) {
gpiod_put(d);
pr_err("No interrupt for UART%d wake GPIO\n", idx + 1);
return;
}
enable_irq_wake(gpiod_to_irq(d));
}
int __init omap_serial_wakeup_init(void)
{
if (!cpu_is_omap16xx())
return 0;
if (uart1_ck != NULL)
omap_serial_set_port_wakeup(0);
if (uart2_ck != NULL)
omap_serial_set_port_wakeup(1);
if (uart3_ck != NULL)
omap_serial_set_port_wakeup(2);
return 0;
}
#endif /* CONFIG_OMAP_SERIAL_WAKE */
static int __init omap_init(void)
{
if (!cpu_class_is_omap1())
return -ENODEV;
return platform_device_register(&serial_device);
}
arch_initcall(omap_init);
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