| Message ID | 1356204719-3317-2-git-send-email-mikedunn@newsguy.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Dear Mike Dunn, I think you should Cc Haojian (done) > This patch gets the LCD working on my Palm Treo680. Changing the Palm > Centro code is avoided (I don't have a Centro for testing at the moment), > but some initialization is shuffled around a bit. I think I have a spare device somewhere around. I might get it available to you somehow eventually -- but that'll need some further discussion. Let's postpone it for now. > This basically adds some code that manages the three gpios that interface > to the lcd on the Treo 680. The precise role of each gpio in the hardware > architecture is not entirely clear to me; this patch is the result of > trial-and-error and observing how the PalmOS code initializes the lcd. Yay, good old times ;-) > The need for this patch is not evident when Linux is loaded from PalmOS, > because at that point the lcd-related gpios have already been configured. > But when booting the kernel by other means, this patch is required unless > the bootloader has performed the necessary initialializations. You mean U-Boot ? Makes sense. [...] > static void __init treo680_init(void) > { > pxa2xx_mfp_config(ARRAY_AND_SIZE(treo680_pin_config)); > palmphone_common_init(); > + treo680_lcd_init(); I think you want to do treo680_gpio_configure() kind of thing and then call palm27x_lcd_init() from here. Even better of course would be to integrate this kind of GPIO fiddling with the backlight subsystem, so the LCD can be properly powered down when going LPM. > palm27x_mmc_init(GPIO_NR_TREO_SD_DETECT_N, GPIO_NR_TREO680_SD_READONLY, > GPIO_NR_TREO680_SD_POWER, 0); > } > @@ -438,6 +488,7 @@ static void __init centro_init(void) > { > pxa2xx_mfp_config(ARRAY_AND_SIZE(centro685_pin_config)); > palmphone_common_init(); > + palm27x_lcd_init(GPIO_NR_TREO_BL_POWER, &palm_320x320_new_lcd_mode); > palm27x_mmc_init(GPIO_NR_TREO_SD_DETECT_N, -1, > GPIO_NR_CENTRO_SD_POWER, 1); > } Best regards, Marek Vasut
On 12/22/2012 07:18 PM, Marek Vasut wrote: > Dear Mike Dunn, > > I think you should Cc Haojian (done) Yes thanks you Marek, and my aplogies Haojian. Actually I was negligent on the CC's of all these patches. When I repost, I'll expand the CC list. [...] > I think I have a spare device somewhere around. I might get it available to you > somehow eventually -- but that'll need some further discussion. Let's postpone > it for now. I plan to start checking ebay soon. The Treos seemed widely available last I checked (at least the 680), and fairly cheap. [...] >> The need for this patch is not evident when Linux is loaded from PalmOS, >> because at that point the lcd-related gpios have already been configured. >> But when booting the kernel by other means, this patch is required unless >> the bootloader has performed the necessary initialializations. > > You mean U-Boot ? Makes sense. Well my u-boot port does initialize the lcd. But generally, it shouldn't be assumed. I discovered the need for this when I loaded the kernel with the emulator. It's actually the secondary program loader that does the initialization (when it displays the Palm logo). > [...] > >> static void __init treo680_init(void) >> { >> pxa2xx_mfp_config(ARRAY_AND_SIZE(treo680_pin_config)); >> palmphone_common_init(); >> + treo680_lcd_init(); > > I think you want to do treo680_gpio_configure() kind of thing and then call > palm27x_lcd_init() from here. I'm not 100% sure, but I think that the lcd controller has to be initialized while the gpios are driven high, then after that, driving one of them low turns the lcd on. This is why palm27x_lcd_init() is called from within treo680_lcd_init(). But yes, it could be cleaner if the hardware permits. I'll experiment some more. > Even better of course would be to integrate this kind of GPIO fiddling with the > backlight subsystem, so the LCD can be properly powered down when going LPM. Yes, this needs to be cleaned up. The label "lcd power" is thrown around too much, sometimes when actually referring to the backlight. And power management is another whole effort. I'm hoping to be able to take things step by step. [...] Thanks for having a look Marek. I'll see if the gpio initialization can be separated from the lcd initialization. MIke
diff --git a/arch/arm/mach-pxa/include/mach/palmtreo.h b/arch/arm/mach-pxa/include/mach/palmtreo.h index 2d3f14e..3266194 100644 --- a/arch/arm/mach-pxa/include/mach/palmtreo.h +++ b/arch/arm/mach-pxa/include/mach/palmtreo.h @@ -44,6 +44,9 @@ #define GPIO_NR_TREO680_VIBRATE_EN 44 #define GPIO_NR_TREO680_KEYB_BL 24 #define GPIO_NR_TREO680_BT_EN 43 +#define GPIO_NR_TREO680_LCD_POWER 77 +#define GPIO_NR_TREO680_LCD_EN 86 +#define GPIO_NR_TREO680_LCD_EN_N 25 #endif /* CONFIG_MACH_TREO680 */ /* Centro685 specific GPIOs */ diff --git a/arch/arm/mach-pxa/palmtreo.c b/arch/arm/mach-pxa/palmtreo.c index 3f3c48f..dcc38a1 100644 --- a/arch/arm/mach-pxa/palmtreo.c +++ b/arch/arm/mach-pxa/palmtreo.c @@ -98,9 +98,6 @@ static unsigned long treo_pin_config[] __initdata = { GPIO96_KP_MKOUT_6, GPIO93_KP_DKIN_0 | WAKEUP_ON_LEVEL_HIGH, /* Hotsync button */ - /* LCD */ - GPIOxx_LCD_TFT_16BPP, - /* Quick Capture Interface */ GPIO84_CIF_FV, GPIO85_CIF_LV, @@ -140,6 +137,12 @@ static unsigned long treo680_pin_config[] __initdata = { /* MATRIX KEYPAD - different wake up source */ GPIO100_KP_MKIN_0 | WAKEUP_ON_LEVEL_HIGH, GPIO99_KP_MKIN_5, + + /* LCD... L_BIAS alt fn not configured on Treo680; is GPIO instead */ + GPIOxx_LCD_16BPP, + GPIO74_LCD_FCLK, + GPIO75_LCD_LCLK, + GPIO76_LCD_PCLK, }; #endif /* CONFIG_MACH_TREO680 */ @@ -155,6 +158,9 @@ static unsigned long centro685_pin_config[] __initdata = { /* MATRIX KEYPAD - different wake up source */ GPIO100_KP_MKIN_0, GPIO99_KP_MKIN_5 | WAKEUP_ON_LEVEL_HIGH, + + /* LCD */ + GPIOxx_LCD_TFT_16BPP, }; #endif /* CONFIG_MACH_CENTRO */ @@ -411,7 +417,6 @@ static void __init palmphone_common_init(void) pxa_set_btuart_info(NULL); pxa_set_stuart_info(NULL); palm27x_pm_init(TREO_STR_BASE); - palm27x_lcd_init(GPIO_NR_TREO_BL_POWER, &palm_320x320_new_lcd_mode); palm27x_udc_init(GPIO_NR_TREO_USB_DETECT, GPIO_NR_TREO_USB_PULLUP, 1); palm27x_irda_init(GPIO_NR_TREO_IR_EN); palm27x_ac97_init(-1, -1, -1, 95); @@ -424,10 +429,55 @@ static void __init palmphone_common_init(void) } #ifdef CONFIG_MACH_TREO680 +void __init treo680_lcd_init(void) +{ + unsigned int gpio; + + /* drive all three gpios high initially */ + const unsigned long flags = GPIOF_INIT_HIGH | GPIOF_DIR_OUT; + + /* + * This is likely the power to the lcd. Toggling it low/high appears to + * turn the lcd off/on. Can be toggled after lcd is initialized without + * any apparent adverse effects to the lcd operation. Note that this + * gpio line is used by the lcd controller as the L_BIAS signal, but + * treo680 configures it as gpio. + */ + gpio = GPIO_NR_TREO680_LCD_POWER; + if (gpio_request_one(gpio, flags, "LCD power") < 0) + goto fail; + + /* + * These two are called enables, for lack of a better understanding. If + * either of these are toggled after the lcd is initialized, the image + * becomes degraded. + */ + gpio = GPIO_NR_TREO680_LCD_EN; + if (gpio_request_one(gpio, flags, "LCD enable") < 0) + goto fail; + gpio = GPIO_NR_TREO680_LCD_EN_N; + if (gpio_request_one(gpio, flags, "LCD enable_n") < 0) + goto fail; + + /* common lcd initialization */ + palm27x_lcd_init(GPIO_NR_TREO_BL_POWER, &palm_320x320_new_lcd_mode); + + /* driving this low turns LCD on */ + gpio_set_value(GPIO_NR_TREO680_LCD_EN_N, 0); + + return; + fail: + pr_err("gpio %d initialization failed\n", gpio); + gpio_free(GPIO_NR_TREO680_LCD_POWER); + gpio_free(GPIO_NR_TREO680_LCD_EN); + gpio_free(GPIO_NR_TREO680_LCD_EN_N); +} + static void __init treo680_init(void) { pxa2xx_mfp_config(ARRAY_AND_SIZE(treo680_pin_config)); palmphone_common_init(); + treo680_lcd_init(); palm27x_mmc_init(GPIO_NR_TREO_SD_DETECT_N, GPIO_NR_TREO680_SD_READONLY, GPIO_NR_TREO680_SD_POWER, 0); } @@ -438,6 +488,7 @@ static void __init centro_init(void) { pxa2xx_mfp_config(ARRAY_AND_SIZE(centro685_pin_config)); palmphone_common_init(); + palm27x_lcd_init(GPIO_NR_TREO_BL_POWER, &palm_320x320_new_lcd_mode); palm27x_mmc_init(GPIO_NR_TREO_SD_DETECT_N, -1, GPIO_NR_CENTRO_SD_POWER, 1); }
This patch gets the LCD working on my Palm Treo680. Changing the Palm Centro code is avoided (I don't have a Centro for testing at the moment), but some initialization is shuffled around a bit. This basically adds some code that manages the three gpios that interface to the lcd on the Treo 680. The precise role of each gpio in the hardware architecture is not entirely clear to me; this patch is the result of trial-and-error and observing how the PalmOS code initializes the lcd. The need for this patch is not evident when Linux is loaded from PalmOS, because at that point the lcd-related gpios have already been configured. But when booting the kernel by other means, this patch is required unless the bootloader has performed the necessary initialializations. Signed-off-by: Mike Dunn <mikedunn@newsguy.com> --- I suspect that at least some of these changes may apply to the Centro as well. When I get a hold of one, I will sort this all out. arch/arm/mach-pxa/include/mach/palmtreo.h | 3 + arch/arm/mach-pxa/palmtreo.c | 59 +++++++++++++++++++++++++++-- 2 files changed, 58 insertions(+), 4 deletions(-)