1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/arch/arm/mach-omap1/serial.c 4 * 5 * OMAP1 serial support. 6 */ 7 #include <linux/gpio.h> 8 #include <linux/module.h> 9 #include <linux/kernel.h> 10 #include <linux/init.h> 11 #include <linux/irq.h> 12 #include <linux/delay.h> 13 #include <linux/serial.h> 14 #include <linux/tty.h> 15 #include <linux/serial_8250.h> 16 #include <linux/serial_reg.h> 17 #include <linux/clk.h> 18 #include <linux/io.h> 19 20 #include <asm/mach-types.h> 21 22 #include "serial.h" 23 #include "mux.h" 24 #include "pm.h" 25 #include "soc.h" 26 27 static struct clk * uart1_ck; 28 static struct clk * uart2_ck; 29 static struct clk * uart3_ck; 30 31 static inline unsigned int omap_serial_in(struct plat_serial8250_port *up, 32 int offset) 33 { 34 offset <<= up->regshift; 35 return (unsigned int)__raw_readb(up->membase + offset); 36 } 37 38 static inline void omap_serial_outp(struct plat_serial8250_port *p, int offset, 39 int value) 40 { 41 offset <<= p->regshift; 42 __raw_writeb(value, p->membase + offset); 43 } 44 45 /* 46 * Internal UARTs need to be initialized for the 8250 autoconfig to work 47 * properly. Note that the TX watermark initialization may not be needed 48 * once the 8250.c watermark handling code is merged. 49 */ 50 static void __init omap_serial_reset(struct plat_serial8250_port *p) 51 { 52 omap_serial_outp(p, UART_OMAP_MDR1, 53 UART_OMAP_MDR1_DISABLE); /* disable UART */ 54 omap_serial_outp(p, UART_OMAP_SCR, 0x08); /* TX watermark */ 55 omap_serial_outp(p, UART_OMAP_MDR1, 56 UART_OMAP_MDR1_16X_MODE); /* enable UART */ 57 58 if (!cpu_is_omap15xx()) { 59 omap_serial_outp(p, UART_OMAP_SYSC, 0x01); 60 while (!(omap_serial_in(p, UART_OMAP_SYSC) & 0x01)); 61 } 62 } 63 64 static struct plat_serial8250_port serial_platform_data[] = { 65 { 66 .mapbase = OMAP1_UART1_BASE, 67 .irq = INT_UART1, 68 .flags = UPF_BOOT_AUTOCONF, 69 .iotype = UPIO_MEM, 70 .regshift = 2, 71 .uartclk = OMAP16XX_BASE_BAUD * 16, 72 }, 73 { 74 .mapbase = OMAP1_UART2_BASE, 75 .irq = INT_UART2, 76 .flags = UPF_BOOT_AUTOCONF, 77 .iotype = UPIO_MEM, 78 .regshift = 2, 79 .uartclk = OMAP16XX_BASE_BAUD * 16, 80 }, 81 { 82 .mapbase = OMAP1_UART3_BASE, 83 .irq = INT_UART3, 84 .flags = UPF_BOOT_AUTOCONF, 85 .iotype = UPIO_MEM, 86 .regshift = 2, 87 .uartclk = OMAP16XX_BASE_BAUD * 16, 88 }, 89 { }, 90 }; 91 92 static struct platform_device serial_device = { 93 .name = "serial8250", 94 .id = PLAT8250_DEV_PLATFORM, 95 .dev = { 96 .platform_data = serial_platform_data, 97 }, 98 }; 99 100 /* 101 * Note that on Innovator-1510 UART2 pins conflict with USB2. 102 * By default UART2 does not work on Innovator-1510 if you have 103 * USB OHCI enabled. To use UART2, you must disable USB2 first. 104 */ 105 void __init omap_serial_init(void) 106 { 107 int i; 108 109 if (cpu_is_omap7xx()) { 110 serial_platform_data[0].regshift = 0; 111 serial_platform_data[1].regshift = 0; 112 serial_platform_data[0].irq = INT_7XX_UART_MODEM_1; 113 serial_platform_data[1].irq = INT_7XX_UART_MODEM_IRDA_2; 114 } 115 116 if (cpu_is_omap15xx()) { 117 serial_platform_data[0].uartclk = OMAP1510_BASE_BAUD * 16; 118 serial_platform_data[1].uartclk = OMAP1510_BASE_BAUD * 16; 119 serial_platform_data[2].uartclk = OMAP1510_BASE_BAUD * 16; 120 } 121 122 for (i = 0; i < ARRAY_SIZE(serial_platform_data) - 1; i++) { 123 124 /* Don't look at UARTs higher than 2 for omap7xx */ 125 if (cpu_is_omap7xx() && i > 1) { 126 serial_platform_data[i].membase = NULL; 127 serial_platform_data[i].mapbase = 0; 128 continue; 129 } 130 131 /* Static mapping, never released */ 132 serial_platform_data[i].membase = 133 ioremap(serial_platform_data[i].mapbase, SZ_2K); 134 if (!serial_platform_data[i].membase) { 135 printk(KERN_ERR "Could not ioremap uart%i\n", i); 136 continue; 137 } 138 switch (i) { 139 case 0: 140 uart1_ck = clk_get(NULL, "uart1_ck"); 141 if (IS_ERR(uart1_ck)) 142 printk("Could not get uart1_ck\n"); 143 else { 144 clk_prepare_enable(uart1_ck); 145 if (cpu_is_omap15xx()) 146 clk_set_rate(uart1_ck, 12000000); 147 } 148 break; 149 case 1: 150 uart2_ck = clk_get(NULL, "uart2_ck"); 151 if (IS_ERR(uart2_ck)) 152 printk("Could not get uart2_ck\n"); 153 else { 154 clk_prepare_enable(uart2_ck); 155 if (cpu_is_omap15xx()) 156 clk_set_rate(uart2_ck, 12000000); 157 else 158 clk_set_rate(uart2_ck, 48000000); 159 } 160 break; 161 case 2: 162 uart3_ck = clk_get(NULL, "uart3_ck"); 163 if (IS_ERR(uart3_ck)) 164 printk("Could not get uart3_ck\n"); 165 else { 166 clk_prepare_enable(uart3_ck); 167 if (cpu_is_omap15xx()) 168 clk_set_rate(uart3_ck, 12000000); 169 } 170 break; 171 } 172 omap_serial_reset(&serial_platform_data[i]); 173 } 174 } 175 176 #ifdef CONFIG_OMAP_SERIAL_WAKE 177 178 static irqreturn_t omap_serial_wake_interrupt(int irq, void *dev_id) 179 { 180 /* Need to do something with serial port right after wake-up? */ 181 return IRQ_HANDLED; 182 } 183 184 /* 185 * Reroutes serial RX lines to GPIO lines for the duration of 186 * sleep to allow waking up the device from serial port even 187 * in deep sleep. 188 */ 189 void omap_serial_wake_trigger(int enable) 190 { 191 if (!cpu_is_omap16xx()) 192 return; 193 194 if (uart1_ck != NULL) { 195 if (enable) 196 omap_cfg_reg(V14_16XX_GPIO37); 197 else 198 omap_cfg_reg(V14_16XX_UART1_RX); 199 } 200 if (uart2_ck != NULL) { 201 if (enable) 202 omap_cfg_reg(R9_16XX_GPIO18); 203 else 204 omap_cfg_reg(R9_16XX_UART2_RX); 205 } 206 if (uart3_ck != NULL) { 207 if (enable) 208 omap_cfg_reg(L14_16XX_GPIO49); 209 else 210 omap_cfg_reg(L14_16XX_UART3_RX); 211 } 212 } 213 214 static void __init omap_serial_set_port_wakeup(int gpio_nr) 215 { 216 int ret; 217 218 ret = gpio_request(gpio_nr, "UART wake"); 219 if (ret < 0) { 220 printk(KERN_ERR "Could not request UART wake GPIO: %i\n", 221 gpio_nr); 222 return; 223 } 224 gpio_direction_input(gpio_nr); 225 ret = request_irq(gpio_to_irq(gpio_nr), &omap_serial_wake_interrupt, 226 IRQF_TRIGGER_RISING, "serial wakeup", NULL); 227 if (ret) { 228 gpio_free(gpio_nr); 229 printk(KERN_ERR "No interrupt for UART wake GPIO: %i\n", 230 gpio_nr); 231 return; 232 } 233 enable_irq_wake(gpio_to_irq(gpio_nr)); 234 } 235 236 int __init omap_serial_wakeup_init(void) 237 { 238 if (!cpu_is_omap16xx()) 239 return 0; 240 241 if (uart1_ck != NULL) 242 omap_serial_set_port_wakeup(37); 243 if (uart2_ck != NULL) 244 omap_serial_set_port_wakeup(18); 245 if (uart3_ck != NULL) 246 omap_serial_set_port_wakeup(49); 247 248 return 0; 249 } 250 251 #endif /* CONFIG_OMAP_SERIAL_WAKE */ 252 253 static int __init omap_init(void) 254 { 255 if (!cpu_class_is_omap1()) 256 return -ENODEV; 257 258 return platform_device_register(&serial_device); 259 } 260 arch_initcall(omap_init); 261