 ca956f0ea8
			
		
	
	
	ca956f0ea8
	
	
	
		
			
			Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
		
			
				
	
	
		
			142 lines
		
	
	
	
		
			3.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			142 lines
		
	
	
	
		
			3.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * AVR power-management chip interface for the Buffalo Linkstation /
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|  * Kurobox Platform.
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|  *
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|  * Author: 2006 (c) G. Liakhovetski
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|  *	 g.liakhovetski@gmx.de
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|  *
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|  * This file is licensed under the terms of the GNU General Public License
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|  * version 2.  This program is licensed "as is" without any warranty of
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|  * any kind, whether express or implied.
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|  */
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| #include <linux/workqueue.h>
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| #include <linux/string.h>
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| #include <linux/delay.h>
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| #include <linux/serial_reg.h>
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| #include <linux/serial_8250.h>
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| #include <asm/io.h>
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| #include <asm/prom.h>
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| #include <asm/termbits.h>
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| 
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| #include "mpc10x.h"
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| 
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| static void __iomem *avr_addr;
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| static unsigned long avr_clock;
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| 
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| static struct work_struct wd_work;
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| 
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| static void wd_stop(struct work_struct *unused)
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| {
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| 	const char string[] = "AAAAFFFFJJJJ>>>>VVVV>>>>ZZZZVVVVKKKK";
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| 	int i = 0, rescue = 8;
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| 	int len = strlen(string);
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| 
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| 	while (rescue--) {
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| 		int j;
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| 		char lsr = in_8(avr_addr + UART_LSR);
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| 
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| 		if (lsr & (UART_LSR_THRE | UART_LSR_TEMT)) {
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| 			for (j = 0; j < 16 && i < len; j++, i++)
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| 				out_8(avr_addr + UART_TX, string[i]);
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| 			if (i == len) {
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| 				/* Read "OK" back: 4ms for the last "KKKK"
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| 				   plus a couple bytes back */
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| 				msleep(7);
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| 				printk("linkstation: disarming the AVR watchdog: ");
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| 				while (in_8(avr_addr + UART_LSR) & UART_LSR_DR)
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| 					printk("%c", in_8(avr_addr + UART_RX));
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| 				break;
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| 			}
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| 		}
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| 		msleep(17);
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| 	}
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| 	printk("\n");
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| }
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| 
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| #define AVR_QUOT(clock) ((clock) + 8 * 9600) / (16 * 9600)
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| 
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| void avr_uart_configure(void)
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| {
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| 	unsigned char cval = UART_LCR_WLEN8;
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| 	unsigned int quot = AVR_QUOT(avr_clock);
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| 
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| 	if (!avr_addr || !avr_clock)
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| 		return;
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| 
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| 	out_8(avr_addr + UART_LCR, cval);			/* initialise UART */
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| 	out_8(avr_addr + UART_MCR, 0);
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| 	out_8(avr_addr + UART_IER, 0);
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| 
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| 	cval |= UART_LCR_STOP | UART_LCR_PARITY | UART_LCR_EPAR;
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| 
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| 	out_8(avr_addr + UART_LCR, cval);			/* Set character format */
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| 
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| 	out_8(avr_addr + UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
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| 	out_8(avr_addr + UART_DLL, quot & 0xff);		/* LS of divisor */
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| 	out_8(avr_addr + UART_DLM, quot >> 8);			/* MS of divisor */
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| 	out_8(avr_addr + UART_LCR, cval);			/* reset DLAB */
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| 	out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO);	/* enable FIFO */
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| }
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| 
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| void avr_uart_send(const char c)
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| {
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| 	if (!avr_addr || !avr_clock)
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| 		return;
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| 
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| 	out_8(avr_addr + UART_TX, c);
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| 	out_8(avr_addr + UART_TX, c);
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| 	out_8(avr_addr + UART_TX, c);
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| 	out_8(avr_addr + UART_TX, c);
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| }
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| 
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| static void __init ls_uart_init(void)
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| {
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| 	local_irq_disable();
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| 
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| #ifndef CONFIG_SERIAL_8250
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| 	out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO);	/* enable FIFO */
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| 	out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO |
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| 	      UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);	/* clear FIFOs */
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| 	out_8(avr_addr + UART_FCR, 0);
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| 	out_8(avr_addr + UART_IER, 0);
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| 
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| 	/* Clear up interrupts */
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| 	(void) in_8(avr_addr + UART_LSR);
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| 	(void) in_8(avr_addr + UART_RX);
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| 	(void) in_8(avr_addr + UART_IIR);
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| 	(void) in_8(avr_addr + UART_MSR);
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| #endif
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| 	avr_uart_configure();
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| 
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| 	local_irq_enable();
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| }
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| 
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| static int __init ls_uarts_init(void)
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| {
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| 	struct device_node *avr;
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| 	phys_addr_t phys_addr;
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| 	int len;
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| 
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| 	avr = of_find_node_by_path("/soc10x/serial@80004500");
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| 	if (!avr)
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| 		return -EINVAL;
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| 
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| 	avr_clock = *(u32*)of_get_property(avr, "clock-frequency", &len);
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| 	phys_addr = ((u32*)of_get_property(avr, "reg", &len))[0];
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| 
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| 	if (!avr_clock || !phys_addr)
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| 		return -EINVAL;
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| 
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| 	avr_addr = ioremap(phys_addr, 32);
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| 	if (!avr_addr)
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| 		return -EFAULT;
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| 
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| 	ls_uart_init();
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| 
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| 	INIT_WORK(&wd_work, wd_stop);
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| 	schedule_work(&wd_work);
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| 
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| 	return 0;
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| }
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| 
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| machine_late_initcall(linkstation, ls_uarts_init);
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