xref: /openbmc/linux/arch/arm/mach-omap1/serial.c (revision fd589a8f)
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 
30 static struct clk * uart1_ck;
31 static struct clk * uart2_ck;
32 static struct clk * uart3_ck;
33 
34 static inline unsigned int omap_serial_in(struct plat_serial8250_port *up,
35 					  int offset)
36 {
37 	offset <<= up->regshift;
38 	return (unsigned int)__raw_readb(up->membase + offset);
39 }
40 
41 static inline void omap_serial_outp(struct plat_serial8250_port *p, int offset,
42 				    int value)
43 {
44 	offset <<= p->regshift;
45 	__raw_writeb(value, p->membase + offset);
46 }
47 
48 /*
49  * Internal UARTs need to be initialized for the 8250 autoconfig to work
50  * properly. Note that the TX watermark initialization may not be needed
51  * once the 8250.c watermark handling code is merged.
52  */
53 static void __init omap_serial_reset(struct plat_serial8250_port *p)
54 {
55 	omap_serial_outp(p, UART_OMAP_MDR1, 0x07);	/* disable UART */
56 	omap_serial_outp(p, UART_OMAP_SCR, 0x08);	/* TX watermark */
57 	omap_serial_outp(p, UART_OMAP_MDR1, 0x00);	/* enable UART */
58 
59 	if (!cpu_is_omap15xx()) {
60 		omap_serial_outp(p, UART_OMAP_SYSC, 0x01);
61 		while (!(omap_serial_in(p, UART_OMAP_SYSC) & 0x01));
62 	}
63 }
64 
65 static struct plat_serial8250_port serial_platform_data[] = {
66 	{
67 		.membase	= OMAP1_IO_ADDRESS(OMAP_UART1_BASE),
68 		.mapbase	= OMAP_UART1_BASE,
69 		.irq		= INT_UART1,
70 		.flags		= UPF_BOOT_AUTOCONF,
71 		.iotype		= UPIO_MEM,
72 		.regshift	= 2,
73 		.uartclk	= OMAP16XX_BASE_BAUD * 16,
74 	},
75 	{
76 		.membase	= OMAP1_IO_ADDRESS(OMAP_UART2_BASE),
77 		.mapbase	= OMAP_UART2_BASE,
78 		.irq		= INT_UART2,
79 		.flags		= UPF_BOOT_AUTOCONF,
80 		.iotype		= UPIO_MEM,
81 		.regshift	= 2,
82 		.uartclk	= OMAP16XX_BASE_BAUD * 16,
83 	},
84 	{
85 		.membase	= OMAP1_IO_ADDRESS(OMAP_UART3_BASE),
86 		.mapbase	= OMAP_UART3_BASE,
87 		.irq		= INT_UART3,
88 		.flags		= UPF_BOOT_AUTOCONF,
89 		.iotype		= UPIO_MEM,
90 		.regshift	= 2,
91 		.uartclk	= OMAP16XX_BASE_BAUD * 16,
92 	},
93 	{ },
94 };
95 
96 static struct platform_device serial_device = {
97 	.name			= "serial8250",
98 	.id			= PLAT8250_DEV_PLATFORM,
99 	.dev			= {
100 		.platform_data	= serial_platform_data,
101 	},
102 };
103 
104 /*
105  * Note that on Innovator-1510 UART2 pins conflict with USB2.
106  * By default UART2 does not work on Innovator-1510 if you have
107  * USB OHCI enabled. To use UART2, you must disable USB2 first.
108  */
109 void __init omap_serial_init(void)
110 {
111 	int i;
112 
113 	if (cpu_is_omap730()) {
114 		serial_platform_data[0].regshift = 0;
115 		serial_platform_data[1].regshift = 0;
116 		serial_platform_data[0].irq = INT_730_UART_MODEM_1;
117 		serial_platform_data[1].irq = INT_730_UART_MODEM_IRDA_2;
118 	}
119 
120 	if (cpu_is_omap850()) {
121 		serial_platform_data[0].regshift = 0;
122 		serial_platform_data[1].regshift = 0;
123 		serial_platform_data[0].irq = INT_850_UART_MODEM_1;
124 		serial_platform_data[1].irq = INT_850_UART_MODEM_IRDA_2;
125 	}
126 
127 	if (cpu_is_omap15xx()) {
128 		serial_platform_data[0].uartclk = OMAP1510_BASE_BAUD * 16;
129 		serial_platform_data[1].uartclk = OMAP1510_BASE_BAUD * 16;
130 		serial_platform_data[2].uartclk = OMAP1510_BASE_BAUD * 16;
131 	}
132 
133 	for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
134 		unsigned char reg;
135 
136 		switch (i) {
137 		case 0:
138 			uart1_ck = clk_get(NULL, "uart1_ck");
139 			if (IS_ERR(uart1_ck))
140 				printk("Could not get uart1_ck\n");
141 			else {
142 				clk_enable(uart1_ck);
143 				if (cpu_is_omap15xx())
144 					clk_set_rate(uart1_ck, 12000000);
145 			}
146 			if (cpu_is_omap15xx()) {
147 				omap_cfg_reg(UART1_TX);
148 				omap_cfg_reg(UART1_RTS);
149 				if (machine_is_omap_innovator()) {
150 					reg = fpga_read(OMAP1510_FPGA_POWER);
151 					reg |= OMAP1510_FPGA_PCR_COM1_EN;
152 					fpga_write(reg, OMAP1510_FPGA_POWER);
153 					udelay(10);
154 				}
155 			}
156 			break;
157 		case 1:
158 			uart2_ck = clk_get(NULL, "uart2_ck");
159 			if (IS_ERR(uart2_ck))
160 				printk("Could not get uart2_ck\n");
161 			else {
162 				clk_enable(uart2_ck);
163 				if (cpu_is_omap15xx())
164 					clk_set_rate(uart2_ck, 12000000);
165 				else
166 					clk_set_rate(uart2_ck, 48000000);
167 			}
168 			if (cpu_is_omap15xx()) {
169 				omap_cfg_reg(UART2_TX);
170 				omap_cfg_reg(UART2_RTS);
171 				if (machine_is_omap_innovator()) {
172 					reg = fpga_read(OMAP1510_FPGA_POWER);
173 					reg |= OMAP1510_FPGA_PCR_COM2_EN;
174 					fpga_write(reg, OMAP1510_FPGA_POWER);
175 					udelay(10);
176 				}
177 			}
178 			break;
179 		case 2:
180 			uart3_ck = clk_get(NULL, "uart3_ck");
181 			if (IS_ERR(uart3_ck))
182 				printk("Could not get uart3_ck\n");
183 			else {
184 				clk_enable(uart3_ck);
185 				if (cpu_is_omap15xx())
186 					clk_set_rate(uart3_ck, 12000000);
187 			}
188 			if (cpu_is_omap15xx()) {
189 				omap_cfg_reg(UART3_TX);
190 				omap_cfg_reg(UART3_RX);
191 			}
192 			break;
193 		}
194 		omap_serial_reset(&serial_platform_data[i]);
195 	}
196 }
197 
198 #ifdef CONFIG_OMAP_SERIAL_WAKE
199 
200 static irqreturn_t omap_serial_wake_interrupt(int irq, void *dev_id)
201 {
202 	/* Need to do something with serial port right after wake-up? */
203 	return IRQ_HANDLED;
204 }
205 
206 /*
207  * Reroutes serial RX lines to GPIO lines for the duration of
208  * sleep to allow waking up the device from serial port even
209  * in deep sleep.
210  */
211 void omap_serial_wake_trigger(int enable)
212 {
213 	if (!cpu_is_omap16xx())
214 		return;
215 
216 	if (uart1_ck != NULL) {
217 		if (enable)
218 			omap_cfg_reg(V14_16XX_GPIO37);
219 		else
220 			omap_cfg_reg(V14_16XX_UART1_RX);
221 	}
222 	if (uart2_ck != NULL) {
223 		if (enable)
224 			omap_cfg_reg(R9_16XX_GPIO18);
225 		else
226 			omap_cfg_reg(R9_16XX_UART2_RX);
227 	}
228 	if (uart3_ck != NULL) {
229 		if (enable)
230 			omap_cfg_reg(L14_16XX_GPIO49);
231 		else
232 			omap_cfg_reg(L14_16XX_UART3_RX);
233 	}
234 }
235 
236 static void __init omap_serial_set_port_wakeup(int gpio_nr)
237 {
238 	int ret;
239 
240 	ret = gpio_request(gpio_nr, "UART wake");
241 	if (ret < 0) {
242 		printk(KERN_ERR "Could not request UART wake GPIO: %i\n",
243 		       gpio_nr);
244 		return;
245 	}
246 	gpio_direction_input(gpio_nr);
247 	ret = request_irq(gpio_to_irq(gpio_nr), &omap_serial_wake_interrupt,
248 			  IRQF_TRIGGER_RISING, "serial wakeup", NULL);
249 	if (ret) {
250 		gpio_free(gpio_nr);
251 		printk(KERN_ERR "No interrupt for UART wake GPIO: %i\n",
252 		       gpio_nr);
253 		return;
254 	}
255 	enable_irq_wake(gpio_to_irq(gpio_nr));
256 }
257 
258 static int __init omap_serial_wakeup_init(void)
259 {
260 	if (!cpu_is_omap16xx())
261 		return 0;
262 
263 	if (uart1_ck != NULL)
264 		omap_serial_set_port_wakeup(37);
265 	if (uart2_ck != NULL)
266 		omap_serial_set_port_wakeup(18);
267 	if (uart3_ck != NULL)
268 		omap_serial_set_port_wakeup(49);
269 
270 	return 0;
271 }
272 late_initcall(omap_serial_wakeup_init);
273 
274 #endif	/* CONFIG_OMAP_SERIAL_WAKE */
275 
276 static int __init omap_init(void)
277 {
278 	return platform_device_register(&serial_device);
279 }
280 arch_initcall(omap_init);
281