1 // SPDX-License-Identifier: GPL-2.0-or-later
3  *    Chassis LCD/LED driver for HP-PARISC workstations
7  *      (c) Copyright 2001-2009 Helge Deller <deller@gmx.de>
11  *	- speed-up calculations with inlined assembler
12  *	- interface to write to second row of LCD from /proc (if technically possible)
15  *      - Audit copy_from_user in led_proc_write.
17  *	- Switch from using a tasklet to a work queue, so the led_LCD_driver
46 #include <asm/led.h>
50 /* The control of the LEDs and LCDs on PARISC-machines have to be done 
56 static int led_type __read_mostly = -1;
57 static unsigned char lastleds;	/* LED state from most recent update */
63 static int  lcd_no_led_support    __read_mostly = 0; /* KittyHawk doesn't support LED on its LCD */
78 	unsigned char on;	/* value for turning LED on     */
79 	unsigned char off;	/* value for turning LED off    */
84    lcd_cmd_reg_addr needs to be 64bit aligned on 64bit PA2.0-machines */
88 	unsigned long lcd_cmd_reg_addr;	/* ptr to LCD cmd-register & data ptr for LED */
89 	unsigned long lcd_data_reg_addr; /* ptr to LCD data-register (LCD only) */
90 	unsigned int min_cmd_delay;	/* delay in uS after cmd-write (LCD only) */
103 #define KITTYHAWK_LCD_CMD  F_EXTEND(0xf0190000UL) /* 64bit-ready */
106 /* lcd_info is pre-initialized to the values needed to program KittyHawk LCD's 
129 /* The workqueue must be created at init-time */
135 	/* KittyHawk has no LED support on its LCD */  in start_task()
138 	/* Create the work queue and queue the LED task */  in start_task()
147 /* ptr to LCD/LED-specific function */
153 	switch ((long)m->private)  in led_proc_show()
179 	char *cur, lbuf[32];  in led_proc_write()  local
183 		return -EACCES;  in led_proc_write()
186 		count = sizeof(lbuf)-1;  in led_proc_write()
189 		return -EFAULT;  in led_proc_write()
192 	cur = lbuf;  in led_proc_write()
197 		d = *cur++ - '0';  in led_proc_write()
201 		if (*cur++ != ' ') goto parse_error;  in led_proc_write()
203 		d = *cur++ - '0';  in led_proc_write()
207 		if (*cur++ != ' ') goto parse_error;  in led_proc_write()
209 		d = *cur++ - '0';  in led_proc_write()
215 		if (*cur && cur[strlen(cur)-1] == '\n')  in led_proc_write()
216 			cur[strlen(cur)-1] = 0;  in led_proc_write()
217 		if (*cur == 0)   in led_proc_write()
218 			cur = lcd_text_default;  in led_proc_write()
219 		lcd_print(cur);  in led_proc_write()
230 	return -EINVAL;  in led_proc_write()
246 	if (led_type == -1) return -1;  in led_create_procfs()
249 	if (!proc_pdc_root) return -1;  in led_create_procfs()
253 		ent = proc_create_data("led", 0644, proc_pdc_root,  in led_create_procfs()
254 					&led_proc_ops, (void *)LED_NOLCD); /* LED */  in led_create_procfs()
255 		if (!ent) return -1;  in led_create_procfs()
262 		if (!ent) return -1;  in led_create_procfs()
328 			gsc_writeb( blockp[i]->command, LCD_CMD_REG );  in led_LCD_driver()
331 			gsc_writeb( leds & mask[i] ? blockp[i]->on :   in led_LCD_driver()
332 					blockp[i]->off, LCD_DATA_REG );  in led_LCD_driver()
343    ** calculate if there was TX- or RX-throughput on the network interfaces
365 	    if (!in_dev || !in_dev->ifa_list)  in led_get_net_activity()
367 	    if (ipv4_is_loopback(in_dev->ifa_list->ifa_local))  in led_get_net_activity()
370 	    rx_total += stats->rx_packets;  in led_get_net_activity()
371 	    tx_total += stats->tx_packets;  in led_get_net_activity()
396    ** calculate if there was disk-io in the system
422    ** manages when and which chassis LCD/LED gets updated
425     - display load average (older machines like 715/64 have 4 "free" LED's for that)
426     - optimizations
446 	count_HZ += jiffies - last_jiffies;  in led_work_func()
453 		/* flash heartbeat-LED like a real heart  in led_work_func()
493    ** LED/LCD activities.
541    ** registers an external LED or LCD for usage by this driver.
542    ** currently only LCD-, LASI- and ASP-style LCD/LED's are supported.
566 		/* Skip to register LED in QEMU */  in register_led_driver()
571 		printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG);  in register_led_driver()
578 		printk(KERN_INFO "LED (ASP-style) display at %lx registered\n",   in register_led_driver()
584 		printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n",  in register_led_driver()
589 	/* mark the LCD/LED driver now as initialized and   in register_led_driver()
605    ** register_led_regions() registers the LCD/LED regions for /procfs.
606    ** At bootup - where the initialisation of the LCD/LED normally happens - 
608    ** so that we delay the led-registration until after busdevices_init() 
632    ** Displays the given string on the LCD-Display of newer machines.
633    ** lcd_print() disables/enables the timer-based led work queue to
644 	/* temporarily disable the led work task */  in lcd_print()
664 	/* re-queue the work */  in lcd_print()
675    ** led_init() is called very early in the bootup-process from setup.c 
676    ** and asks the PDC for an usable chassis LCD or LED.
677    ** If the PDC doesn't return any info, then the LED
690 		"Linux %s", init_utsname()->release);  in led_init()
692 	/* Work around the buggy PDC of KittyHawk-machines */  in led_init()
694 	case 0x580:		/* KittyHawk DC2-100 (K100) */  in led_init()
695 	case 0x581:		/* KittyHawk DC3-120 (K210) */  in led_init()
699 		printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, "  in led_init()
700 				"LED detection skipped.\n", __FILE__, CPU_HVERSION);  in led_init()
716 			  (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown",  in led_init()
732 				offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1)  in led_init()
740 		case DISPLAY_MODEL_NONE:	/* no LED or LCD available */  in led_init()
741 			printk(KERN_INFO "PDC reported no LCD or LED.\n");  in led_init()
744 		case DISPLAY_MODEL_LASI:	/* Lasi style 8 bit LED display */  in led_init()
750 			printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n",  in led_init()
756 		/* register the LCD/LED driver */  in led_init()