// SPDX-License-Identifier: GPL-2.0-or-later /* * Chassis LCD/LED driver for HP-PARISC workstations * * (c) Copyright 2000 Red Hat Software * (c) Copyright 2000 Helge Deller * (c) Copyright 2001 Randolph Chung * (c) Copyright 2000-2023 Helge Deller * * The control of the LEDs and LCDs on PARISC machines has to be done * completely in software. * * The LEDs can be configured at runtime in /sys/class/leds/ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* HZ */ #include #include #define LED_HAS_LCD 1 #define LED_HAS_LED 2 static unsigned char led_type; /* bitmask of LED_HAS_XXX */ static unsigned char lastleds; /* LED state from most recent update */ static unsigned char lcd_new_text; static unsigned char lcd_text[20]; static unsigned char lcd_text_default[20]; static unsigned char lcd_no_led_support; /* KittyHawk doesn't support LED on its LCD */ struct lcd_block { unsigned char command; /* stores the command byte */ unsigned char on; /* value for turning LED on */ unsigned char off; /* value for turning LED off */ }; /* Structure returned by PDC_RETURN_CHASSIS_INFO */ /* NOTE: we use unsigned long:16 two times, since the following member lcd_cmd_reg_addr needs to be 64bit aligned on 64bit PA2.0-machines */ struct pdc_chassis_lcd_info_ret_block { unsigned long model:16; /* DISPLAY_MODEL_XXXX */ unsigned long lcd_width:16; /* width of the LCD in chars (DISPLAY_MODEL_LCD only) */ unsigned long lcd_cmd_reg_addr; /* ptr to LCD cmd-register & data ptr for LED */ unsigned long lcd_data_reg_addr; /* ptr to LCD data-register (LCD only) */ unsigned int min_cmd_delay; /* delay in uS after cmd-write (LCD only) */ unsigned char reset_cmd1; /* command #1 for writing LCD string (LCD only) */ unsigned char reset_cmd2; /* command #2 for writing LCD string (LCD only) */ unsigned char act_enable; /* 0 = no activity (LCD only) */ struct lcd_block heartbeat; struct lcd_block disk_io; struct lcd_block lan_rcv; struct lcd_block lan_tx; char _pad; }; /* LCD_CMD and LCD_DATA for KittyHawk machines */ #define KITTYHAWK_LCD_CMD F_EXTEND(0xf0190000UL) #define KITTYHAWK_LCD_DATA (KITTYHAWK_LCD_CMD + 1) /* lcd_info is pre-initialized to the values needed to program KittyHawk LCD's * HP seems to have used Sharp/Hitachi HD44780 LCDs most of the time. */ static struct pdc_chassis_lcd_info_ret_block lcd_info __attribute__((aligned(8))) = { .model = DISPLAY_MODEL_NONE, .lcd_width = 16, .lcd_cmd_reg_addr = KITTYHAWK_LCD_CMD, .lcd_data_reg_addr = KITTYHAWK_LCD_DATA, .min_cmd_delay = 80, .reset_cmd1 = 0x80, .reset_cmd2 = 0xc0, }; /* direct access to some of the lcd_info variables */ #define LCD_CMD_REG lcd_info.lcd_cmd_reg_addr #define LCD_DATA_REG lcd_info.lcd_data_reg_addr #define LED_DATA_REG lcd_info.lcd_cmd_reg_addr /* LASI & ASP only */ /* ptr to LCD/LED-specific function */ static void (*led_func_ptr) (unsigned char); static void lcd_print_now(void) { int i; char *str = lcd_text; if (lcd_info.model != DISPLAY_MODEL_LCD) return; if (!lcd_new_text) return; lcd_new_text = 0; /* Set LCD Cursor to 1st character */ gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG); udelay(lcd_info.min_cmd_delay); /* Print the string */ for (i = 0; i < lcd_info.lcd_width; i++) { gsc_writeb(*str ? *str++ : ' ', LCD_DATA_REG); udelay(lcd_info.min_cmd_delay); } } /** * lcd_print() * * @str: string to show on the LCD. If NULL, print current string again. * * Displays the given string on the LCD-Display of newer machines. */ void lcd_print(const char *str) { /* copy display string to buffer for procfs */ if (str) strscpy(lcd_text, str, sizeof(lcd_text)); lcd_new_text = 1; /* print now if LCD without any LEDs */ if (led_type == LED_HAS_LCD) lcd_print_now(); } #define LED_DATA 0x01 /* data to shift (0:on 1:off) */ #define LED_STROBE 0x02 /* strobe to clock data */ /** * led_ASP_driver() - LED driver for the ASP controller chip * * @leds: bitmap representing the LED status */ static void led_ASP_driver(unsigned char leds) { int i; leds = ~leds; for (i = 0; i < 8; i++) { unsigned char value; value = (leds & 0x80) >> 7; gsc_writeb( value, LED_DATA_REG ); gsc_writeb( value | LED_STROBE, LED_DATA_REG ); leds <<= 1; } } /** * led_LASI_driver() - LED driver for the LASI controller chip * * @leds: bitmap representing the LED status */ static void led_LASI_driver(unsigned char leds) { leds = ~leds; gsc_writeb( leds, LED_DATA_REG ); } /** * led_LCD_driver() - LED & LCD driver for LCD chips * * @leds: bitmap representing the LED status */ static void led_LCD_driver(unsigned char leds) { static const unsigned char mask[4] = { LED_HEARTBEAT, LED_DISK_IO, LED_LAN_RCV, LED_LAN_TX }; static struct lcd_block * const blockp[4] = { &lcd_info.heartbeat, &lcd_info.disk_io, &lcd_info.lan_rcv, &lcd_info.lan_tx }; static unsigned char latest_leds; int i; for (i = 0; i < 4; ++i) { if ((leds & mask[i]) == (latest_leds & mask[i])) continue; gsc_writeb( blockp[i]->command, LCD_CMD_REG ); udelay(lcd_info.min_cmd_delay); gsc_writeb( leds & mask[i] ? blockp[i]->on : blockp[i]->off, LCD_DATA_REG ); udelay(lcd_info.min_cmd_delay); } latest_leds = leds; lcd_print_now(); } /** * lcd_system_halt() * * @nb: pointer to the notifier_block structure * @event: the event (SYS_RESTART, SYS_HALT or SYS_POWER_OFF) * @buf: pointer to a buffer (not used) * * Called by the reboot notifier chain at shutdown. Stops all * LED/LCD activities. */ static int lcd_system_halt(struct notifier_block *nb, unsigned long event, void *buf) { const char *txt; switch (event) { case SYS_RESTART: txt = "SYSTEM RESTART"; break; case SYS_HALT: txt = "SYSTEM HALT"; break; case SYS_POWER_OFF: txt = "SYSTEM POWER OFF"; break; default: return NOTIFY_DONE; } lcd_print(txt); return NOTIFY_OK; } static struct notifier_block lcd_system_halt_notifier = { .notifier_call = lcd_system_halt, }; static void set_led(struct led_classdev *led_cdev, enum led_brightness brightness); struct hppa_led { struct led_classdev led_cdev; unsigned char led_bit; }; #define to_hppa_led(d) container_of(d, struct hppa_led, led_cdev) typedef void (*set_handler)(struct led_classdev *, enum led_brightness); struct led_type { const char *name; set_handler handler; const char *default_trigger; }; #define NUM_LEDS_PER_BOARD 8 struct hppa_drvdata { struct hppa_led leds[NUM_LEDS_PER_BOARD]; }; static void set_led(struct led_classdev *led_cdev, enum led_brightness brightness) { struct hppa_led *p = to_hppa_led(led_cdev); unsigned char led_bit = p->led_bit; if (brightness == LED_OFF) lastleds &= ~led_bit; else lastleds |= led_bit; if (led_func_ptr) led_func_ptr(lastleds); } static int hppa_led_generic_probe(struct platform_device *pdev, struct led_type *types) { struct hppa_drvdata *p; int i, err; p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL); if (!p) return -ENOMEM; for (i = 0; i < NUM_LEDS_PER_BOARD; i++) { struct led_classdev *lp = &p->leds[i].led_cdev; p->leds[i].led_bit = BIT(i); lp->name = types[i].name; lp->brightness = LED_FULL; lp->brightness_set = types[i].handler; lp->default_trigger = types[i].default_trigger; err = led_classdev_register(&pdev->dev, lp); if (err) { dev_err(&pdev->dev, "Could not register %s LED\n", lp->name); for (i--; i >= 0; i--) led_classdev_unregister(&p->leds[i].led_cdev); return err; } } platform_set_drvdata(pdev, p); return 0; } static void platform_led_remove(struct platform_device *pdev) { struct hppa_drvdata *p = platform_get_drvdata(pdev); int i; for (i = 0; i < NUM_LEDS_PER_BOARD; i++) led_classdev_unregister(&p->leds[i].led_cdev); } static struct led_type mainboard_led_types[NUM_LEDS_PER_BOARD] = { { .name = "platform-lan-tx", .handler = set_led, .default_trigger = "tx", }, { .name = "platform-lan-rx", .handler = set_led, .default_trigger = "rx", }, { .name = "platform-disk", .handler = set_led, .default_trigger = "disk-activity", }, { .name = "platform-heartbeat", .handler = set_led, .default_trigger = "heartbeat", }, { .name = "platform-LED4", .handler = set_led, .default_trigger = "panic", }, { .name = "platform-LED5", .handler = set_led, .default_trigger = "panic", }, { .name = "platform-LED6", .handler = set_led, .default_trigger = "panic", }, { .name = "platform-LED7", .handler = set_led, .default_trigger = "panic", }, }; static int platform_led_probe(struct platform_device *pdev) { return hppa_led_generic_probe(pdev, mainboard_led_types); } MODULE_ALIAS("platform:platform-leds"); static struct platform_driver hppa_mainboard_led_driver = { .probe = platform_led_probe, .remove_new = platform_led_remove, .driver = { .name = "platform-leds", }, }; static struct platform_driver * const drivers[] = { &hppa_mainboard_led_driver, }; static struct platform_device platform_leds = { .name = "platform-leds", }; /** * register_led_driver() * * @model: model type, one of the DISPLAY_MODEL_XXXX values * @cmd_reg: physical address of cmd register for the LED/LCD * @data_reg: physical address of data register for the LED/LCD * * Registers a chassis LED or LCD which should be driven by this driver. * Only PDC-based, LASI- or ASP-style LEDs and LCDs are supported. */ int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg) { if (led_func_ptr || !data_reg) return 1; /* No LEDs when running in QEMU */ if (running_on_qemu) return 1; lcd_info.model = model; /* store the values */ LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg; switch (lcd_info.model) { case DISPLAY_MODEL_LCD: LCD_DATA_REG = data_reg; pr_info("led: LCD display at %#lx and %#lx\n", LCD_CMD_REG , LCD_DATA_REG); led_func_ptr = led_LCD_driver; if (lcd_no_led_support) led_type = LED_HAS_LCD; else led_type = LED_HAS_LCD | LED_HAS_LED; break; case DISPLAY_MODEL_LASI: LED_DATA_REG = data_reg; led_func_ptr = led_LASI_driver; pr_info("led: LED display at %#lx\n", LED_DATA_REG); led_type = LED_HAS_LED; break; case DISPLAY_MODEL_OLD_ASP: LED_DATA_REG = data_reg; led_func_ptr = led_ASP_driver; pr_info("led: LED (ASP-style) display at %#lx\n", LED_DATA_REG); led_type = LED_HAS_LED; break; default: pr_err("led: Unknown LCD/LED model type %d\n", lcd_info.model); return 1; } platform_register_drivers(drivers, ARRAY_SIZE(drivers)); return register_reboot_notifier(&lcd_system_halt_notifier); } /** * early_led_init() * * early_led_init() is called early in the bootup-process and asks the * PDC for an usable chassis LCD or LED. If the PDC doesn't return any * info, then a LED might be detected by the LASI or ASP drivers later. * KittyHawk machines have often a buggy PDC, so that we explicitly check * for those machines here. */ static int __init early_led_init(void) { struct pdc_chassis_info chassis_info; int ret; snprintf(lcd_text_default, sizeof(lcd_text_default), "Linux %s", init_utsname()->release); strcpy(lcd_text, lcd_text_default); lcd_new_text = 1; /* Work around the buggy PDC of KittyHawk-machines */ switch (CPU_HVERSION) { case 0x580: /* KittyHawk DC2-100 (K100) */ case 0x581: /* KittyHawk DC3-120 (K210) */ case 0x582: /* KittyHawk DC3 100 (K400) */ case 0x583: /* KittyHawk DC3 120 (K410) */ case 0x58B: /* KittyHawk DC2 100 (K200) */ pr_info("LCD on KittyHawk-Machine found.\n"); lcd_info.model = DISPLAY_MODEL_LCD; /* KittyHawk has no LED support on its LCD, so skip LED detection */ lcd_no_led_support = 1; goto found; /* use the preinitialized values of lcd_info */ } /* initialize the struct, so that we can check for valid return values */ chassis_info.actcnt = chassis_info.maxcnt = 0; ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info)); if (ret != PDC_OK) { not_found: lcd_info.model = DISPLAY_MODEL_NONE; return 1; } /* check the results. Some machines have a buggy PDC */ if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt) goto not_found; switch (lcd_info.model) { case DISPLAY_MODEL_LCD: /* LCD display */ if (chassis_info.actcnt < offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1) goto not_found; if (!lcd_info.act_enable) { /* PDC tells LCD should not be used. */ goto not_found; } break; case DISPLAY_MODEL_NONE: /* no LED or LCD available */ goto not_found; case DISPLAY_MODEL_LASI: /* Lasi style 8 bit LED display */ if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32) goto not_found; break; default: pr_warn("PDC reported unknown LCD/LED model %d\n", lcd_info.model); goto not_found; } found: /* register the LCD/LED driver */ return register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG); } arch_initcall(early_led_init); /** * register_led_regions() * * Register_led_regions() registers the LCD/LED regions for /procfs. * At bootup - where the initialisation of the LCD/LED often happens * not all internal structures of request_region() are properly set up, * so that we delay the led-registration until after busdevices_init() * has been executed. */ static void __init register_led_regions(void) { switch (lcd_info.model) { case DISPLAY_MODEL_LCD: request_mem_region((unsigned long)LCD_CMD_REG, 1, "lcd_cmd"); request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data"); break; case DISPLAY_MODEL_LASI: case DISPLAY_MODEL_OLD_ASP: request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data"); break; } } static int __init startup_leds(void) { if (platform_device_register(&platform_leds)) printk(KERN_INFO "LED: failed to register LEDs\n"); register_led_regions(); return 0; } device_initcall(startup_leds);