fbtft-bus.c (7736B)
1// SPDX-License-Identifier: GPL-2.0 2#include <linux/export.h> 3#include <linux/errno.h> 4#include <linux/gpio/consumer.h> 5#include <linux/spi/spi.h> 6#include "fbtft.h" 7 8/***************************************************************************** 9 * 10 * void (*write_reg)(struct fbtft_par *par, int len, ...); 11 * 12 *****************************************************************************/ 13 14#define define_fbtft_write_reg(func, buffer_type, data_type, modifier) \ 15void func(struct fbtft_par *par, int len, ...) \ 16{ \ 17 va_list args; \ 18 int i, ret; \ 19 int offset = 0; \ 20 buffer_type *buf = (buffer_type *)par->buf; \ 21 \ 22 if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) { \ 23 va_start(args, len); \ 24 for (i = 0; i < len; i++) { \ 25 buf[i] = modifier((data_type)va_arg(args, \ 26 unsigned int)); \ 27 } \ 28 va_end(args); \ 29 fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, \ 30 par->info->device, buffer_type, buf, len, \ 31 "%s: ", __func__); \ 32 } \ 33 \ 34 va_start(args, len); \ 35 \ 36 if (par->startbyte) { \ 37 *(u8 *)par->buf = par->startbyte; \ 38 buf = (buffer_type *)(par->buf + 1); \ 39 offset = 1; \ 40 } \ 41 \ 42 *buf = modifier((data_type)va_arg(args, unsigned int)); \ 43 ret = fbtft_write_buf_dc(par, par->buf, sizeof(data_type) + offset, \ 44 0); \ 45 if (ret < 0) \ 46 goto out; \ 47 len--; \ 48 \ 49 if (par->startbyte) \ 50 *(u8 *)par->buf = par->startbyte | 0x2; \ 51 \ 52 if (len) { \ 53 i = len; \ 54 while (i--) \ 55 *buf++ = modifier((data_type)va_arg(args, \ 56 unsigned int)); \ 57 fbtft_write_buf_dc(par, par->buf, \ 58 len * (sizeof(data_type) + offset), 1); \ 59 } \ 60out: \ 61 va_end(args); \ 62} \ 63EXPORT_SYMBOL(func); 64 65define_fbtft_write_reg(fbtft_write_reg8_bus8, u8, u8, ) 66define_fbtft_write_reg(fbtft_write_reg16_bus8, __be16, u16, cpu_to_be16) 67define_fbtft_write_reg(fbtft_write_reg16_bus16, u16, u16, ) 68 69void fbtft_write_reg8_bus9(struct fbtft_par *par, int len, ...) 70{ 71 va_list args; 72 int i, ret; 73 int pad = 0; 74 u16 *buf = (u16 *)par->buf; 75 76 if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) { 77 va_start(args, len); 78 for (i = 0; i < len; i++) 79 *(((u8 *)buf) + i) = (u8)va_arg(args, unsigned int); 80 va_end(args); 81 fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, 82 par->info->device, u8, buf, len, "%s: ", 83 __func__); 84 } 85 if (len <= 0) 86 return; 87 88 if (par->spi && (par->spi->bits_per_word == 8)) { 89 /* we're emulating 9-bit, pad start of buffer with no-ops 90 * (assuming here that zero is a no-op) 91 */ 92 pad = (len % 4) ? 4 - (len % 4) : 0; 93 for (i = 0; i < pad; i++) 94 *buf++ = 0x000; 95 } 96 97 va_start(args, len); 98 *buf++ = (u8)va_arg(args, unsigned int); 99 i = len - 1; 100 while (i--) { 101 *buf = (u8)va_arg(args, unsigned int); 102 *buf++ |= 0x100; /* dc=1 */ 103 } 104 va_end(args); 105 ret = par->fbtftops.write(par, par->buf, (len + pad) * sizeof(u16)); 106 if (ret < 0) { 107 dev_err(par->info->device, 108 "write() failed and returned %d\n", ret); 109 return; 110 } 111} 112EXPORT_SYMBOL(fbtft_write_reg8_bus9); 113 114/***************************************************************************** 115 * 116 * int (*write_vmem)(struct fbtft_par *par); 117 * 118 *****************************************************************************/ 119 120/* 16 bit pixel over 8-bit databus */ 121int fbtft_write_vmem16_bus8(struct fbtft_par *par, size_t offset, size_t len) 122{ 123 u16 *vmem16; 124 __be16 *txbuf16 = par->txbuf.buf; 125 size_t remain; 126 size_t to_copy; 127 size_t tx_array_size; 128 int i; 129 int ret = 0; 130 size_t startbyte_size = 0; 131 132 fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s(offset=%zu, len=%zu)\n", 133 __func__, offset, len); 134 135 remain = len / 2; 136 vmem16 = (u16 *)(par->info->screen_buffer + offset); 137 138 gpiod_set_value(par->gpio.dc, 1); 139 140 /* non buffered write */ 141 if (!par->txbuf.buf) 142 return par->fbtftops.write(par, vmem16, len); 143 144 /* buffered write */ 145 tx_array_size = par->txbuf.len / 2; 146 147 if (par->startbyte) { 148 txbuf16 = par->txbuf.buf + 1; 149 tx_array_size -= 2; 150 *(u8 *)(par->txbuf.buf) = par->startbyte | 0x2; 151 startbyte_size = 1; 152 } 153 154 while (remain) { 155 to_copy = min(tx_array_size, remain); 156 dev_dbg(par->info->device, "to_copy=%zu, remain=%zu\n", 157 to_copy, remain - to_copy); 158 159 for (i = 0; i < to_copy; i++) 160 txbuf16[i] = cpu_to_be16(vmem16[i]); 161 162 vmem16 = vmem16 + to_copy; 163 ret = par->fbtftops.write(par, par->txbuf.buf, 164 startbyte_size + to_copy * 2); 165 if (ret < 0) 166 return ret; 167 remain -= to_copy; 168 } 169 170 return ret; 171} 172EXPORT_SYMBOL(fbtft_write_vmem16_bus8); 173 174/* 16 bit pixel over 9-bit SPI bus: dc + high byte, dc + low byte */ 175int fbtft_write_vmem16_bus9(struct fbtft_par *par, size_t offset, size_t len) 176{ 177 u8 *vmem8; 178 u16 *txbuf16 = par->txbuf.buf; 179 size_t remain; 180 size_t to_copy; 181 size_t tx_array_size; 182 int i; 183 int ret = 0; 184 185 fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s(offset=%zu, len=%zu)\n", 186 __func__, offset, len); 187 188 if (!par->txbuf.buf) { 189 dev_err(par->info->device, "%s: txbuf.buf is NULL\n", __func__); 190 return -1; 191 } 192 193 remain = len; 194 vmem8 = par->info->screen_buffer + offset; 195 196 tx_array_size = par->txbuf.len / 2; 197 198 while (remain) { 199 to_copy = min(tx_array_size, remain); 200 dev_dbg(par->info->device, "to_copy=%zu, remain=%zu\n", 201 to_copy, remain - to_copy); 202 203#ifdef __LITTLE_ENDIAN 204 for (i = 0; i < to_copy; i += 2) { 205 txbuf16[i] = 0x0100 | vmem8[i + 1]; 206 txbuf16[i + 1] = 0x0100 | vmem8[i]; 207 } 208#else 209 for (i = 0; i < to_copy; i++) 210 txbuf16[i] = 0x0100 | vmem8[i]; 211#endif 212 vmem8 = vmem8 + to_copy; 213 ret = par->fbtftops.write(par, par->txbuf.buf, to_copy * 2); 214 if (ret < 0) 215 return ret; 216 remain -= to_copy; 217 } 218 219 return ret; 220} 221EXPORT_SYMBOL(fbtft_write_vmem16_bus9); 222 223int fbtft_write_vmem8_bus8(struct fbtft_par *par, size_t offset, size_t len) 224{ 225 dev_err(par->info->device, "%s: function not implemented\n", __func__); 226 return -1; 227} 228EXPORT_SYMBOL(fbtft_write_vmem8_bus8); 229 230/* 16 bit pixel over 16-bit databus */ 231int fbtft_write_vmem16_bus16(struct fbtft_par *par, size_t offset, size_t len) 232{ 233 u16 *vmem16; 234 235 fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s(offset=%zu, len=%zu)\n", 236 __func__, offset, len); 237 238 vmem16 = (u16 *)(par->info->screen_buffer + offset); 239 240 /* no need for buffered write with 16-bit bus */ 241 return fbtft_write_buf_dc(par, vmem16, len, 1); 242} 243EXPORT_SYMBOL(fbtft_write_vmem16_bus16);