From 735ce95e6b9a262d1fbc0ddb5620deb3a29d1067 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Tue, 8 May 2007 00:32:13 -0700 Subject: minor spi_butterfly cleanup Simplify the spi_butterfly driver by removing incomplete/unused support for the second SPI bus, implemented by the USI controller. This should make this a clearer example of how to write a parport bitbang driver. Signed-off-by: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/spi/spi_butterfly.c | 62 +++------------------------------------------ 1 file changed, 4 insertions(+), 58 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/spi_butterfly.c b/drivers/spi/spi_butterfly.c index 574d0fa..0ee2b20 100644 --- a/drivers/spi/spi_butterfly.c +++ b/drivers/spi/spi_butterfly.c @@ -40,8 +40,6 @@ * and use this custom parallel port cable. */ -#undef HAVE_USI /* nyet */ - /* DATA output bits (pins 2..9 == D0..D7) */ #define butterfly_nreset (1 << 1) /* pin 3 */ @@ -49,19 +47,13 @@ #define spi_sck_bit (1 << 0) /* pin 2 */ #define spi_mosi_bit (1 << 7) /* pin 9 */ -#define usi_sck_bit (1 << 3) /* pin 5 */ -#define usi_mosi_bit (1 << 4) /* pin 6 */ - #define vcc_bits ((1 << 6) | (1 << 5)) /* pins 7, 8 */ /* STATUS input bits */ #define spi_miso_bit PARPORT_STATUS_BUSY /* pin 11 */ -#define usi_miso_bit PARPORT_STATUS_PAPEROUT /* pin 12 */ - /* CONTROL output bits */ #define spi_cs_bit PARPORT_CONTROL_SELECT /* pin 17 */ -/* USI uses no chipselect */ @@ -70,15 +62,6 @@ static inline struct butterfly *spidev_to_pp(struct spi_device *spi) return spi->controller_data; } -static inline int is_usidev(struct spi_device *spi) -{ -#ifdef HAVE_USI - return spi->chip_select != 1; -#else - return 0; -#endif -} - struct butterfly { /* REVISIT ... for now, this must be first */ @@ -97,23 +80,13 @@ struct butterfly { /*----------------------------------------------------------------------*/ -/* - * these routines may be slower than necessary because they're hiding - * the fact that there are two different SPI busses on this cable: one - * to the DataFlash chip (or AVR SPI controller), the other to the - * AVR USI controller. - */ - static inline void setsck(struct spi_device *spi, int is_on) { struct butterfly *pp = spidev_to_pp(spi); u8 bit, byte = pp->lastbyte; - if (is_usidev(spi)) - bit = usi_sck_bit; - else - bit = spi_sck_bit; + bit = spi_sck_bit; if (is_on) byte |= bit; @@ -129,10 +102,7 @@ setmosi(struct spi_device *spi, int is_on) struct butterfly *pp = spidev_to_pp(spi); u8 bit, byte = pp->lastbyte; - if (is_usidev(spi)) - bit = usi_mosi_bit; - else - bit = spi_mosi_bit; + bit = spi_mosi_bit; if (is_on) byte |= bit; @@ -148,10 +118,7 @@ static inline int getmiso(struct spi_device *spi) int value; u8 bit; - if (is_usidev(spi)) - bit = usi_miso_bit; - else - bit = spi_miso_bit; + bit = spi_miso_bit; /* only STATUS_BUSY is NOT negated */ value = !(parport_read_status(pp->port) & bit); @@ -166,10 +133,6 @@ static void butterfly_chipselect(struct spi_device *spi, int value) if (value != BITBANG_CS_INACTIVE) setsck(spi, spi->mode & SPI_CPOL); - /* no chipselect on this USI link config */ - if (is_usidev(spi)) - return; - /* here, value == "activate or not"; * most PARPORT_CONTROL_* bits are negated, so we must * morph it to value == "bit value to write in control register" @@ -292,7 +255,7 @@ static void butterfly_attach(struct parport *p) parport_frob_control(pp->port, spi_cs_bit, 0); /* stabilize power with chip in reset (nRESET), and - * both spi_sck_bit and usi_sck_bit clear (CPOL=0) + * spi_sck_bit clear (CPOL=0) */ pp->lastbyte |= vcc_bits; parport_write_data(pp->port, pp->lastbyte); @@ -326,23 +289,6 @@ static void butterfly_attach(struct parport *p) pr_debug("%s: dataflash at %s\n", p->name, pp->dataflash->dev.bus_id); -#ifdef HAVE_USI - /* Bus 2 is only for talking to the AVR, and it can work no - * matter who masters bus 1; needs appropriate AVR firmware. - */ - pp->info[1].max_speed_hz = 10 /* ?? */ * 1000 * 1000; - strcpy(pp->info[1].modalias, "butterfly"); - // pp->info[1].platform_data = ... TBD ... ; - pp->info[1].chip_select = 2, - pp->info[1].controller_data = pp; - pp->butterfly = spi_new_device(pp->bitbang.master, &pp->info[1]); - if (pp->butterfly) - pr_debug("%s: butterfly at %s\n", p->name, - pp->butterfly->dev.bus_id); - - /* FIXME setup ACK for the IRQ line ... */ -#endif - // dev_info(_what?_, ...) pr_info("%s: AVR Butterfly\n", p->name); butterfly = pp; -- cgit v1.1