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Release 4.7 drivers/staging/fbtft/fbtft-io.c

#include <linux/export.h>
#include <linux/errno.h>
#include <linux/gpio.h>
#include <linux/spi/spi.h>
#include "fbtft.h"


int fbtft_write_spi(struct fbtft_par *par, void *buf, size_t len) { struct spi_transfer t = { .tx_buf = buf, .len = len, }; struct spi_message m; fbtft_par_dbg_hex(DEBUG_WRITE, par, par->info->device, u8, buf, len, "%s(len=%d): ", __func__, len); if (!par->spi) { dev_err(par->info->device, "%s: par->spi is unexpectedly NULL\n", __func__); return -1; } spi_message_init(&m); if (par->txbuf.dma && buf == par->txbuf.buf) { t.tx_dma = par->txbuf.dma; m.is_dma_mapped = 1; } spi_message_add_tail(&t, &m); return spi_sync(par->spi, &m); }

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thomas petazzonithomas petazzoni148100.00%1100.00%
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EXPORT_SYMBOL(fbtft_write_spi); /** * fbtft_write_spi_emulate_9() - write SPI emulating 9-bit * @par: Driver data * @buf: Buffer to write * @len: Length of buffer (must be divisible by 8) * * When 9-bit SPI is not available, this function can be used to emulate that. * par->extra must hold a transformation buffer used for transfer. */
int fbtft_write_spi_emulate_9(struct fbtft_par *par, void *buf, size_t len) { u16 *src = buf; u8 *dst = par->extra; size_t size = len / 2; size_t added = 0; int bits, i, j; u64 val, dc, tmp; fbtft_par_dbg_hex(DEBUG_WRITE, par, par->info->device, u8, buf, len, "%s(len=%d): ", __func__, len); if (!par->extra) { dev_err(par->info->device, "%s: error: par->extra is NULL\n", __func__); return -EINVAL; } if ((len % 8) != 0) { dev_err(par->info->device, "error: len=%zu must be divisible by 8\n", len); return -EINVAL; } for (i = 0; i < size; i += 8) { tmp = 0; bits = 63; for (j = 0; j < 7; j++) { dc = (*src & 0x0100) ? 1 : 0; val = *src & 0x00FF; tmp |= dc << bits; bits -= 8; tmp |= val << bits--; src++; } tmp |= ((*src & 0x0100) ? 1 : 0); *(u64 *)dst = cpu_to_be64(tmp); dst += 8; *dst++ = (u8)(*src++ & 0x00FF); added++; } return spi_write(par->spi, par->extra, size + added); }

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thomas petazzonithomas petazzoni28099.64%150.00%
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Total281100.00%2100.00%

EXPORT_SYMBOL(fbtft_write_spi_emulate_9);
int fbtft_read_spi(struct fbtft_par *par, void *buf, size_t len) { int ret; u8 txbuf[32] = { 0, }; struct spi_transfer t = { .speed_hz = 2000000, .rx_buf = buf, .len = len, }; struct spi_message m; if (!par->spi) { dev_err(par->info->device, "%s: par->spi is unexpectedly NULL\n", __func__); return -ENODEV; } if (par->startbyte) { if (len > 32) { dev_err(par->info->device, "len=%zu can't be larger than 32 when using 'startbyte'\n", len); return -EINVAL; } txbuf[0] = par->startbyte | 0x3; t.tx_buf = txbuf; fbtft_par_dbg_hex(DEBUG_READ, par, par->info->device, u8, txbuf, len, "%s(len=%d) txbuf => ", __func__, len); } spi_message_init(&m); spi_message_add_tail(&t, &m); ret = spi_sync(par->spi, &m); fbtft_par_dbg_hex(DEBUG_READ, par, par->info->device, u8, buf, len, "%s(len=%d) buf <= ", __func__, len); return ret; }

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thomas petazzonithomas petazzoni21099.53%150.00%
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Total211100.00%2100.00%

EXPORT_SYMBOL(fbtft_read_spi); /* * Optimized use of gpiolib is twice as fast as no optimization * only one driver can use the optimized version at a time */
int fbtft_write_gpio8_wr(struct fbtft_par *par, void *buf, size_t len) { u8 data; int i; #ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO static u8 prev_data; #endif fbtft_par_dbg_hex(DEBUG_WRITE, par, par->info->device, u8, buf, len, "%s(len=%d): ", __func__, len); while (len--) { data = *(u8 *)buf; /* Start writing by pulling down /WR */ gpio_set_value(par->gpio.wr, 0); /* Set data */ #ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO if (data == prev_data) { gpio_set_value(par->gpio.wr, 0); /* used as delay */ } else { for (i = 0; i < 8; i++) { if ((data & 1) != (prev_data & 1)) gpio_set_value(par->gpio.db[i], data & 1); data >>= 1; prev_data >>= 1; } } #else for (i = 0; i < 8; i++) { gpio_set_value(par->gpio.db[i], data & 1); data >>= 1; } #endif /* Pullup /WR */ gpio_set_value(par->gpio.wr, 1); #ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO prev_data = *(u8 *)buf; #endif buf++; } return 0; }

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thomas petazzonithomas petazzoni13255.93%150.00%
noralf tronnesnoralf tronnes10444.07%150.00%
Total236100.00%2100.00%

EXPORT_SYMBOL(fbtft_write_gpio8_wr);
int fbtft_write_gpio16_wr(struct fbtft_par *par, void *buf, size_t len) { u16 data; int i; #ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO static u16 prev_data; #endif fbtft_par_dbg_hex(DEBUG_WRITE, par, par->info->device, u8, buf, len, "%s(len=%d): ", __func__, len); while (len) { data = *(u16 *)buf; /* Start writing by pulling down /WR */ gpio_set_value(par->gpio.wr, 0); /* Set data */ #ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO if (data == prev_data) { gpio_set_value(par->gpio.wr, 0); /* used as delay */ } else { for (i = 0; i < 16; i++) { if ((data & 1) != (prev_data & 1)) gpio_set_value(par->gpio.db[i], data & 1); data >>= 1; prev_data >>= 1; } } #else for (i = 0; i < 16; i++) { gpio_set_value(par->gpio.db[i], data & 1); data >>= 1; } #endif /* Pullup /WR */ gpio_set_value(par->gpio.wr, 1); #ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO prev_data = *(u16 *)buf; #endif buf += 2; len -= 2; } return 0; }

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thomas petazzonithomas petazzoni23095.83%150.00%
noralf tronnesnoralf tronnes104.17%150.00%
Total240100.00%2100.00%

EXPORT_SYMBOL(fbtft_write_gpio16_wr);
int fbtft_write_gpio16_wr_latched(struct fbtft_par *par, void *buf, size_t len) { dev_err(par->info->device, "%s: function not implemented\n", __func__); return -1; }

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thomas petazzonithomas petazzoni34100.00%1100.00%
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EXPORT_SYMBOL(fbtft_write_gpio16_wr_latched);

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thomas petazzonithomas petazzoni108090.23%133.33%
noralf tronnesnoralf tronnes1159.61%133.33%
haneen mohammedhaneen mohammed20.17%133.33%
Total1197100.00%3100.00%
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