FreeCalypso > hg > freecalypso-tools
changeset 502:cb33d81f1386
pirexplore SPCA552E init delays changed from bogo-ms to true ms
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Mon, 27 May 2019 02:01:26 +0000 |
| parents | 7a6eba04c1bb |
| children | da53ea0a38ba |
| files | target-utils/pirexplore/lcd.c |
| diffstat | 1 files changed, 14 insertions(+), 5 deletions(-) [+] |
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--- a/target-utils/pirexplore/lcd.c Mon May 27 01:12:43 2019 +0000 +++ b/target-utils/pirexplore/lcd.c Mon May 27 02:01:26 2019 +0000 @@ -9,6 +9,8 @@ #define nCS4_ADDR0 (*(volatile u16 *)0x02800000) #define nCS4_ADDR2 (*(volatile u16 *)0x02800002) +#define DELAY_1MS 13000 + fb_spca_write(addr, data) { GPIO_OUT_REG &= 0xFF7F; @@ -45,17 +47,24 @@ */ GPIO_OUT_REG = 0x0000; GPIO_OUT_REG = 0x0012; - /* non-understandable voodoo copied from OsmocomBB */ + /* + * The non-understandable voodoo that follows has been copied from + * OsmocomBB, and more recently has been updated to use true ms + * delays instead of bogo-ms. OBB's original code used their + * delay_ms() function, but the latter implements a delay in + * bogo-milliseconds instead of true ms, with 1 bogo-ms equal to + * 400 us in actual physical time. + */ fb_spca_write(0x7e, 0x00); /* internal register access */ - osmo_delay_ms(10); + wait_ARM_cycles(DELAY_1MS * 4); /* 10 bogo-ms = 4 ms */ fb_spca_write(0x7a, 0x00); /* keep CPU in reset state */ - osmo_delay_ms(10); + wait_ARM_cycles(DELAY_1MS * 4); /* 10 bogo-ms = 4 ms */ fb_spca_write(0x7f, 0x00); /* select main page */ - osmo_delay_ms(5); + wait_ARM_cycles(DELAY_1MS * 2); /* 5 bogo-ms = 2 ms */ fb_spca_write(0x72, 0x07); /* don't reshape timing, 16 bit mode */ fb_spca_write(0x14, 0x03); fb_spca_write(0x7f, 0x00); /* select main page */ - osmo_delay_ms(5); + wait_ARM_cycles(DELAY_1MS * 2); /* 5 bogo-ms = 2 ms */ fb_spca_write(0x06, 0xff); fb_spca_write(0x7f, 0x09); fb_spca_write(0x19, 0x08); /* backlight: 0x08 is on, 0x0c is off */