xref: /openbmc/linux/arch/arm/mach-omap1/serial.c (revision b04b4f78)
1 /*
2  * linux/arch/arm/mach-omap1/serial.c
3  *
4  * OMAP1 serial support.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/irq.h>
15 #include <linux/delay.h>
16 #include <linux/serial.h>
17 #include <linux/tty.h>
18 #include <linux/serial_8250.h>
19 #include <linux/serial_reg.h>
20 #include <linux/clk.h>
21 #include <linux/io.h>
22 
23 #include <asm/mach-types.h>
24 
25 #include <mach/board.h>
26 #include <mach/mux.h>
27 #include <mach/gpio.h>
28 #include <mach/fpga.h>
29 #ifdef CONFIG_PM
30 #include <mach/pm.h>
31 #endif
32 
33 static struct clk * uart1_ck;
34 static struct clk * uart2_ck;
35 static struct clk * uart3_ck;
36 
37 static inline unsigned int omap_serial_in(struct plat_serial8250_port *up,
38 					  int offset)
39 {
40 	offset <<= up->regshift;
41 	return (unsigned int)__raw_readb(up->membase + offset);
42 }
43 
44 static inline void omap_serial_outp(struct plat_serial8250_port *p, int offset,
45 				    int value)
46 {
47 	offset <<= p->regshift;
48 	__raw_writeb(value, p->membase + offset);
49 }
50 
51 /*
52  * Internal UARTs need to be initialized for the 8250 autoconfig to work
53  * properly. Note that the TX watermark initialization may not be needed
54  * once the 8250.c watermark handling code is merged.
55  */
56 static void __init omap_serial_reset(struct plat_serial8250_port *p)
57 {
58 	omap_serial_outp(p, UART_OMAP_MDR1, 0x07);	/* disable UART */
59 	omap_serial_outp(p, UART_OMAP_SCR, 0x08);	/* TX watermark */
60 	omap_serial_outp(p, UART_OMAP_MDR1, 0x00);	/* enable UART */
61 
62 	if (!cpu_is_omap15xx()) {
63 		omap_serial_outp(p, UART_OMAP_SYSC, 0x01);
64 		while (!(omap_serial_in(p, UART_OMAP_SYSC) & 0x01));
65 	}
66 }
67 
68 static struct plat_serial8250_port serial_platform_data[] = {
69 	{
70 		.membase	= IO_ADDRESS(OMAP_UART1_BASE),
71 		.mapbase	= OMAP_UART1_BASE,
72 		.irq		= INT_UART1,
73 		.flags		= UPF_BOOT_AUTOCONF,
74 		.iotype		= UPIO_MEM,
75 		.regshift	= 2,
76 		.uartclk	= OMAP16XX_BASE_BAUD * 16,
77 	},
78 	{
79 		.membase	= IO_ADDRESS(OMAP_UART2_BASE),
80 		.mapbase	= OMAP_UART2_BASE,
81 		.irq		= INT_UART2,
82 		.flags		= UPF_BOOT_AUTOCONF,
83 		.iotype		= UPIO_MEM,
84 		.regshift	= 2,
85 		.uartclk	= OMAP16XX_BASE_BAUD * 16,
86 	},
87 	{
88 		.membase	= IO_ADDRESS(OMAP_UART3_BASE),
89 		.mapbase	= OMAP_UART3_BASE,
90 		.irq		= INT_UART3,
91 		.flags		= UPF_BOOT_AUTOCONF,
92 		.iotype		= UPIO_MEM,
93 		.regshift	= 2,
94 		.uartclk	= OMAP16XX_BASE_BAUD * 16,
95 	},
96 	{ },
97 };
98 
99 static struct platform_device serial_device = {
100 	.name			= "serial8250",
101 	.id			= PLAT8250_DEV_PLATFORM,
102 	.dev			= {
103 		.platform_data	= serial_platform_data,
104 	},
105 };
106 
107 /*
108  * Note that on Innovator-1510 UART2 pins conflict with USB2.
109  * By default UART2 does not work on Innovator-1510 if you have
110  * USB OHCI enabled. To use UART2, you must disable USB2 first.
111  */
112 void __init omap_serial_init(void)
113 {
114 	int i;
115 	const struct omap_uart_config *info;
116 
117 	if (cpu_is_omap730()) {
118 		serial_platform_data[0].regshift = 0;
119 		serial_platform_data[1].regshift = 0;
120 		serial_platform_data[0].irq = INT_730_UART_MODEM_1;
121 		serial_platform_data[1].irq = INT_730_UART_MODEM_IRDA_2;
122 	}
123 
124 	if (cpu_is_omap850()) {
125 		serial_platform_data[0].regshift = 0;
126 		serial_platform_data[1].regshift = 0;
127 		serial_platform_data[0].irq = INT_850_UART_MODEM_1;
128 		serial_platform_data[1].irq = INT_850_UART_MODEM_IRDA_2;
129 	}
130 
131 	if (cpu_is_omap15xx()) {
132 		serial_platform_data[0].uartclk = OMAP1510_BASE_BAUD * 16;
133 		serial_platform_data[1].uartclk = OMAP1510_BASE_BAUD * 16;
134 		serial_platform_data[2].uartclk = OMAP1510_BASE_BAUD * 16;
135 	}
136 
137 	info = omap_get_config(OMAP_TAG_UART, struct omap_uart_config);
138 	if (info == NULL)
139 		return;
140 
141 	for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
142 		unsigned char reg;
143 
144 		if (!((1 << i) & info->enabled_uarts)) {
145 			serial_platform_data[i].membase = NULL;
146 			serial_platform_data[i].mapbase = 0;
147 			continue;
148 		}
149 
150 		switch (i) {
151 		case 0:
152 			uart1_ck = clk_get(NULL, "uart1_ck");
153 			if (IS_ERR(uart1_ck))
154 				printk("Could not get uart1_ck\n");
155 			else {
156 				clk_enable(uart1_ck);
157 				if (cpu_is_omap15xx())
158 					clk_set_rate(uart1_ck, 12000000);
159 			}
160 			if (cpu_is_omap15xx()) {
161 				omap_cfg_reg(UART1_TX);
162 				omap_cfg_reg(UART1_RTS);
163 				if (machine_is_omap_innovator()) {
164 					reg = fpga_read(OMAP1510_FPGA_POWER);
165 					reg |= OMAP1510_FPGA_PCR_COM1_EN;
166 					fpga_write(reg, OMAP1510_FPGA_POWER);
167 					udelay(10);
168 				}
169 			}
170 			break;
171 		case 1:
172 			uart2_ck = clk_get(NULL, "uart2_ck");
173 			if (IS_ERR(uart2_ck))
174 				printk("Could not get uart2_ck\n");
175 			else {
176 				clk_enable(uart2_ck);
177 				if (cpu_is_omap15xx())
178 					clk_set_rate(uart2_ck, 12000000);
179 				else
180 					clk_set_rate(uart2_ck, 48000000);
181 			}
182 			if (cpu_is_omap15xx()) {
183 				omap_cfg_reg(UART2_TX);
184 				omap_cfg_reg(UART2_RTS);
185 				if (machine_is_omap_innovator()) {
186 					reg = fpga_read(OMAP1510_FPGA_POWER);
187 					reg |= OMAP1510_FPGA_PCR_COM2_EN;
188 					fpga_write(reg, OMAP1510_FPGA_POWER);
189 					udelay(10);
190 				}
191 			}
192 			break;
193 		case 2:
194 			uart3_ck = clk_get(NULL, "uart3_ck");
195 			if (IS_ERR(uart3_ck))
196 				printk("Could not get uart3_ck\n");
197 			else {
198 				clk_enable(uart3_ck);
199 				if (cpu_is_omap15xx())
200 					clk_set_rate(uart3_ck, 12000000);
201 			}
202 			if (cpu_is_omap15xx()) {
203 				omap_cfg_reg(UART3_TX);
204 				omap_cfg_reg(UART3_RX);
205 			}
206 			break;
207 		}
208 		omap_serial_reset(&serial_platform_data[i]);
209 	}
210 }
211 
212 #ifdef CONFIG_OMAP_SERIAL_WAKE
213 
214 static irqreturn_t omap_serial_wake_interrupt(int irq, void *dev_id)
215 {
216 	/* Need to do something with serial port right after wake-up? */
217 	return IRQ_HANDLED;
218 }
219 
220 /*
221  * Reroutes serial RX lines to GPIO lines for the duration of
222  * sleep to allow waking up the device from serial port even
223  * in deep sleep.
224  */
225 void omap_serial_wake_trigger(int enable)
226 {
227 	if (!cpu_is_omap16xx())
228 		return;
229 
230 	if (uart1_ck != NULL) {
231 		if (enable)
232 			omap_cfg_reg(V14_16XX_GPIO37);
233 		else
234 			omap_cfg_reg(V14_16XX_UART1_RX);
235 	}
236 	if (uart2_ck != NULL) {
237 		if (enable)
238 			omap_cfg_reg(R9_16XX_GPIO18);
239 		else
240 			omap_cfg_reg(R9_16XX_UART2_RX);
241 	}
242 	if (uart3_ck != NULL) {
243 		if (enable)
244 			omap_cfg_reg(L14_16XX_GPIO49);
245 		else
246 			omap_cfg_reg(L14_16XX_UART3_RX);
247 	}
248 }
249 
250 static void __init omap_serial_set_port_wakeup(int gpio_nr)
251 {
252 	int ret;
253 
254 	ret = gpio_request(gpio_nr, "UART wake");
255 	if (ret < 0) {
256 		printk(KERN_ERR "Could not request UART wake GPIO: %i\n",
257 		       gpio_nr);
258 		return;
259 	}
260 	gpio_direction_input(gpio_nr);
261 	ret = request_irq(gpio_to_irq(gpio_nr), &omap_serial_wake_interrupt,
262 			  IRQF_TRIGGER_RISING, "serial wakeup", NULL);
263 	if (ret) {
264 		gpio_free(gpio_nr);
265 		printk(KERN_ERR "No interrupt for UART wake GPIO: %i\n",
266 		       gpio_nr);
267 		return;
268 	}
269 	enable_irq_wake(gpio_to_irq(gpio_nr));
270 }
271 
272 static int __init omap_serial_wakeup_init(void)
273 {
274 	if (!cpu_is_omap16xx())
275 		return 0;
276 
277 	if (uart1_ck != NULL)
278 		omap_serial_set_port_wakeup(37);
279 	if (uart2_ck != NULL)
280 		omap_serial_set_port_wakeup(18);
281 	if (uart3_ck != NULL)
282 		omap_serial_set_port_wakeup(49);
283 
284 	return 0;
285 }
286 late_initcall(omap_serial_wakeup_init);
287 
288 #endif	/* CONFIG_OMAP_SERIAL_WAKE */
289 
290 static int __init omap_init(void)
291 {
292 	return platform_device_register(&serial_device);
293 }
294 arch_initcall(omap_init);
295