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_omap15xx()) { 110 serial_platform_data[0].uartclk = OMAP1510_BASE_BAUD * 16; 111 serial_platform_data[1].uartclk = OMAP1510_BASE_BAUD * 16; 112 serial_platform_data[2].uartclk = OMAP1510_BASE_BAUD * 16; 113 } 114 115 for (i = 0; i < ARRAY_SIZE(serial_platform_data) - 1; i++) { 116 /* Static mapping, never released */ 117 serial_platform_data[i].membase = 118 ioremap(serial_platform_data[i].mapbase, SZ_2K); 119 if (!serial_platform_data[i].membase) { 120 printk(KERN_ERR "Could not ioremap uart%i\n", i); 121 continue; 122 } 123 switch (i) { 124 case 0: 125 uart1_ck = clk_get(NULL, "uart1_ck"); 126 if (IS_ERR(uart1_ck)) 127 printk("Could not get uart1_ck\n"); 128 else { 129 clk_prepare_enable(uart1_ck); 130 if (cpu_is_omap15xx()) 131 clk_set_rate(uart1_ck, 12000000); 132 } 133 break; 134 case 1: 135 uart2_ck = clk_get(NULL, "uart2_ck"); 136 if (IS_ERR(uart2_ck)) 137 printk("Could not get uart2_ck\n"); 138 else { 139 clk_prepare_enable(uart2_ck); 140 if (cpu_is_omap15xx()) 141 clk_set_rate(uart2_ck, 12000000); 142 else 143 clk_set_rate(uart2_ck, 48000000); 144 } 145 break; 146 case 2: 147 uart3_ck = clk_get(NULL, "uart3_ck"); 148 if (IS_ERR(uart3_ck)) 149 printk("Could not get uart3_ck\n"); 150 else { 151 clk_prepare_enable(uart3_ck); 152 if (cpu_is_omap15xx()) 153 clk_set_rate(uart3_ck, 12000000); 154 } 155 break; 156 } 157 omap_serial_reset(&serial_platform_data[i]); 158 } 159 } 160 161 #ifdef CONFIG_OMAP_SERIAL_WAKE 162 163 static irqreturn_t omap_serial_wake_interrupt(int irq, void *dev_id) 164 { 165 /* Need to do something with serial port right after wake-up? */ 166 return IRQ_HANDLED; 167 } 168 169 /* 170 * Reroutes serial RX lines to GPIO lines for the duration of 171 * sleep to allow waking up the device from serial port even 172 * in deep sleep. 173 */ 174 void omap_serial_wake_trigger(int enable) 175 { 176 if (!cpu_is_omap16xx()) 177 return; 178 179 if (uart1_ck != NULL) { 180 if (enable) 181 omap_cfg_reg(V14_16XX_GPIO37); 182 else 183 omap_cfg_reg(V14_16XX_UART1_RX); 184 } 185 if (uart2_ck != NULL) { 186 if (enable) 187 omap_cfg_reg(R9_16XX_GPIO18); 188 else 189 omap_cfg_reg(R9_16XX_UART2_RX); 190 } 191 if (uart3_ck != NULL) { 192 if (enable) 193 omap_cfg_reg(L14_16XX_GPIO49); 194 else 195 omap_cfg_reg(L14_16XX_UART3_RX); 196 } 197 } 198 199 static void __init omap_serial_set_port_wakeup(int gpio_nr) 200 { 201 int ret; 202 203 ret = gpio_request(gpio_nr, "UART wake"); 204 if (ret < 0) { 205 printk(KERN_ERR "Could not request UART wake GPIO: %i\n", 206 gpio_nr); 207 return; 208 } 209 gpio_direction_input(gpio_nr); 210 ret = request_irq(gpio_to_irq(gpio_nr), &omap_serial_wake_interrupt, 211 IRQF_TRIGGER_RISING, "serial wakeup", NULL); 212 if (ret) { 213 gpio_free(gpio_nr); 214 printk(KERN_ERR "No interrupt for UART wake GPIO: %i\n", 215 gpio_nr); 216 return; 217 } 218 enable_irq_wake(gpio_to_irq(gpio_nr)); 219 } 220 221 int __init omap_serial_wakeup_init(void) 222 { 223 if (!cpu_is_omap16xx()) 224 return 0; 225 226 if (uart1_ck != NULL) 227 omap_serial_set_port_wakeup(37); 228 if (uart2_ck != NULL) 229 omap_serial_set_port_wakeup(18); 230 if (uart3_ck != NULL) 231 omap_serial_set_port_wakeup(49); 232 233 return 0; 234 } 235 236 #endif /* CONFIG_OMAP_SERIAL_WAKE */ 237 238 static int __init omap_init(void) 239 { 240 if (!cpu_class_is_omap1()) 241 return -ENODEV; 242 243 return platform_device_register(&serial_device); 244 } 245 arch_initcall(omap_init); 246