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/machine.h> 8 #include <linux/gpio/consumer.h> 9 #include <linux/module.h> 10 #include <linux/kernel.h> 11 #include <linux/init.h> 12 #include <linux/irq.h> 13 #include <linux/delay.h> 14 #include <linux/serial.h> 15 #include <linux/tty.h> 16 #include <linux/serial_8250.h> 17 #include <linux/serial_reg.h> 18 #include <linux/clk.h> 19 #include <linux/io.h> 20 21 #include <asm/mach-types.h> 22 23 #include "common.h" 24 #include "serial.h" 25 #include "mux.h" 26 #include "pm.h" 27 #include "soc.h" 28 29 static struct clk * uart1_ck; 30 static struct clk * uart2_ck; 31 static struct clk * uart3_ck; 32 33 static inline unsigned int omap_serial_in(struct plat_serial8250_port *up, 34 int offset) 35 { 36 offset <<= up->regshift; 37 return (unsigned int)__raw_readb(up->membase + offset); 38 } 39 40 static inline void omap_serial_outp(struct plat_serial8250_port *p, int offset, 41 int value) 42 { 43 offset <<= p->regshift; 44 __raw_writeb(value, p->membase + offset); 45 } 46 47 /* 48 * Internal UARTs need to be initialized for the 8250 autoconfig to work 49 * properly. Note that the TX watermark initialization may not be needed 50 * once the 8250.c watermark handling code is merged. 51 */ 52 static void __init omap_serial_reset(struct plat_serial8250_port *p) 53 { 54 omap_serial_outp(p, UART_OMAP_MDR1, 55 UART_OMAP_MDR1_DISABLE); /* disable UART */ 56 omap_serial_outp(p, UART_OMAP_SCR, 0x08); /* TX watermark */ 57 omap_serial_outp(p, UART_OMAP_MDR1, 58 UART_OMAP_MDR1_16X_MODE); /* enable UART */ 59 60 if (!cpu_is_omap15xx()) { 61 omap_serial_outp(p, UART_OMAP_SYSC, 0x01); 62 while (!(omap_serial_in(p, UART_OMAP_SYSC) & 0x01)); 63 } 64 } 65 66 static struct plat_serial8250_port serial_platform_data[] = { 67 { 68 .mapbase = OMAP1_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 .mapbase = OMAP1_UART2_BASE, 77 .irq = INT_UART2, 78 .flags = UPF_BOOT_AUTOCONF, 79 .iotype = UPIO_MEM, 80 .regshift = 2, 81 .uartclk = OMAP16XX_BASE_BAUD * 16, 82 }, 83 { 84 .mapbase = OMAP1_UART3_BASE, 85 .irq = INT_UART3, 86 .flags = UPF_BOOT_AUTOCONF, 87 .iotype = UPIO_MEM, 88 .regshift = 2, 89 .uartclk = OMAP16XX_BASE_BAUD * 16, 90 }, 91 { }, 92 }; 93 94 static struct platform_device serial_device = { 95 .name = "serial8250", 96 .id = PLAT8250_DEV_PLATFORM, 97 .dev = { 98 .platform_data = serial_platform_data, 99 }, 100 }; 101 102 /* 103 * Note that on Innovator-1510 UART2 pins conflict with USB2. 104 * By default UART2 does not work on Innovator-1510 if you have 105 * USB OHCI enabled. To use UART2, you must disable USB2 first. 106 */ 107 void __init omap_serial_init(void) 108 { 109 int i; 110 111 if (cpu_is_omap15xx()) { 112 serial_platform_data[0].uartclk = OMAP1510_BASE_BAUD * 16; 113 serial_platform_data[1].uartclk = OMAP1510_BASE_BAUD * 16; 114 serial_platform_data[2].uartclk = OMAP1510_BASE_BAUD * 16; 115 } 116 117 for (i = 0; i < ARRAY_SIZE(serial_platform_data) - 1; i++) { 118 /* Static mapping, never released */ 119 serial_platform_data[i].membase = 120 ioremap(serial_platform_data[i].mapbase, SZ_2K); 121 if (!serial_platform_data[i].membase) { 122 printk(KERN_ERR "Could not ioremap uart%i\n", i); 123 continue; 124 } 125 switch (i) { 126 case 0: 127 uart1_ck = clk_get(NULL, "uart1_ck"); 128 if (IS_ERR(uart1_ck)) 129 printk("Could not get uart1_ck\n"); 130 else { 131 clk_prepare_enable(uart1_ck); 132 if (cpu_is_omap15xx()) 133 clk_set_rate(uart1_ck, 12000000); 134 } 135 break; 136 case 1: 137 uart2_ck = clk_get(NULL, "uart2_ck"); 138 if (IS_ERR(uart2_ck)) 139 printk("Could not get uart2_ck\n"); 140 else { 141 clk_prepare_enable(uart2_ck); 142 if (cpu_is_omap15xx()) 143 clk_set_rate(uart2_ck, 12000000); 144 else 145 clk_set_rate(uart2_ck, 48000000); 146 } 147 break; 148 case 2: 149 uart3_ck = clk_get(NULL, "uart3_ck"); 150 if (IS_ERR(uart3_ck)) 151 printk("Could not get uart3_ck\n"); 152 else { 153 clk_prepare_enable(uart3_ck); 154 if (cpu_is_omap15xx()) 155 clk_set_rate(uart3_ck, 12000000); 156 } 157 break; 158 } 159 omap_serial_reset(&serial_platform_data[i]); 160 } 161 } 162 163 #ifdef CONFIG_OMAP_SERIAL_WAKE 164 165 static irqreturn_t omap_serial_wake_interrupt(int irq, void *dev_id) 166 { 167 /* Need to do something with serial port right after wake-up? */ 168 return IRQ_HANDLED; 169 } 170 171 /* 172 * Reroutes serial RX lines to GPIO lines for the duration of 173 * sleep to allow waking up the device from serial port even 174 * in deep sleep. 175 */ 176 void omap_serial_wake_trigger(int enable) 177 { 178 if (!cpu_is_omap16xx()) 179 return; 180 181 if (uart1_ck != NULL) { 182 if (enable) 183 omap_cfg_reg(V14_16XX_GPIO37); 184 else 185 omap_cfg_reg(V14_16XX_UART1_RX); 186 } 187 if (uart2_ck != NULL) { 188 if (enable) 189 omap_cfg_reg(R9_16XX_GPIO18); 190 else 191 omap_cfg_reg(R9_16XX_UART2_RX); 192 } 193 if (uart3_ck != NULL) { 194 if (enable) 195 omap_cfg_reg(L14_16XX_GPIO49); 196 else 197 omap_cfg_reg(L14_16XX_UART3_RX); 198 } 199 } 200 201 static void __init omap_serial_set_port_wakeup(int idx) 202 { 203 struct gpio_desc *d; 204 int ret; 205 206 d = gpiod_get_index(NULL, "wakeup", idx, GPIOD_IN); 207 if (IS_ERR(d)) { 208 pr_err("Unable to get UART wakeup GPIO descriptor\n"); 209 return; 210 } 211 ret = request_irq(gpiod_to_irq(d), &omap_serial_wake_interrupt, 212 IRQF_TRIGGER_RISING, "serial wakeup", NULL); 213 if (ret) { 214 gpiod_put(d); 215 pr_err("No interrupt for UART%d wake GPIO\n", idx + 1); 216 return; 217 } 218 enable_irq_wake(gpiod_to_irq(d)); 219 } 220 221 222 int __init omap_serial_wakeup_init(void) 223 { 224 if (!cpu_is_omap16xx()) 225 return 0; 226 227 if (uart1_ck != NULL) 228 omap_serial_set_port_wakeup(0); 229 if (uart2_ck != NULL) 230 omap_serial_set_port_wakeup(1); 231 if (uart3_ck != NULL) 232 omap_serial_set_port_wakeup(2); 233 234 return 0; 235 } 236 237 #endif /* CONFIG_OMAP_SERIAL_WAKE */ 238 239 static int __init omap_init(void) 240 { 241 if (!cpu_class_is_omap1()) 242 return -ENODEV; 243 244 return platform_device_register(&serial_device); 245 } 246 arch_initcall(omap_init); 247