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>
8 /*****************************************************************************
10 * void (*write_reg)(struct fbtft_par *par, int len, ...);
12 *****************************************************************************/
14 #define define_fbtft_write_reg(func, buffer_type, data_type, modifier) \
15 void func(struct fbtft_par *par, int len, ...) \
20 buffer_type *buf = (buffer_type *)par->buf; \
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, \
29 fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, \
30 par->info->device, buffer_type, buf, len, \
34 va_start(args, len); \
36 if (par->startbyte) { \
37 *(u8 *)par->buf = par->startbyte; \
38 buf = (buffer_type *)(par->buf + 1); \
42 *buf = modifier((data_type)va_arg(args, unsigned int)); \
43 ret = fbtft_write_buf_dc(par, par->buf, sizeof(data_type) + offset, \
50 *(u8 *)par->buf = par->startbyte | 0x2; \
55 *buf++ = modifier((data_type)va_arg(args, \
57 fbtft_write_buf_dc(par, par->buf, \
58 len * (sizeof(data_type) + offset), 1); \
65 define_fbtft_write_reg(fbtft_write_reg8_bus8, u8, u8, )
66 define_fbtft_write_reg(fbtft_write_reg16_bus8, __be16, u16, cpu_to_be16)
67 define_fbtft_write_reg(fbtft_write_reg16_bus16, u16, u16, )
69 void fbtft_write_reg8_bus9(struct fbtft_par *par, int len, ...)
74 u16 *buf = (u16 *)par->buf;
76 if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) {
78 for (i = 0; i < len; i++)
79 *(((u8 *)buf) + i) = (u8)va_arg(args, unsigned int);
81 fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par,
82 par->info->device, u8, buf, len, "%s: ",
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)
92 pad = (len % 4) ? 4 - (len % 4) : 0;
93 for (i = 0; i < pad; i++)
98 *buf++ = (u8)va_arg(args, unsigned int);
101 *buf = (u8)va_arg(args, unsigned int);
102 *buf++ |= 0x100; /* dc=1 */
105 ret = par->fbtftops.write(par, par->buf, (len + pad) * sizeof(u16));
107 dev_err(par->info->device,
108 "write() failed and returned %d\n", ret);
112 EXPORT_SYMBOL(fbtft_write_reg8_bus9);
114 /*****************************************************************************
116 * int (*write_vmem)(struct fbtft_par *par);
118 *****************************************************************************/
120 /* 16 bit pixel over 8-bit databus */
121 int fbtft_write_vmem16_bus8(struct fbtft_par *par, size_t offset, size_t len)
124 __be16 *txbuf16 = par->txbuf.buf;
127 size_t tx_array_size;
130 size_t startbyte_size = 0;
132 fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s(offset=%zu, len=%zu)\n",
133 __func__, offset, len);
136 vmem16 = (u16 *)(par->info->screen_buffer + offset);
138 gpiod_set_value(par->gpio.dc, 1);
140 /* non buffered write */
142 return par->fbtftops.write(par, vmem16, len);
145 tx_array_size = par->txbuf.len / 2;
147 if (par->startbyte) {
148 txbuf16 = par->txbuf.buf + 1;
150 *(u8 *)(par->txbuf.buf) = par->startbyte | 0x2;
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);
159 for (i = 0; i < to_copy; i++)
160 txbuf16[i] = cpu_to_be16(vmem16[i]);
162 vmem16 = vmem16 + to_copy;
163 ret = par->fbtftops.write(par, par->txbuf.buf,
164 startbyte_size + to_copy * 2);
172 EXPORT_SYMBOL(fbtft_write_vmem16_bus8);
174 /* 16 bit pixel over 9-bit SPI bus: dc + high byte, dc + low byte */
175 int fbtft_write_vmem16_bus9(struct fbtft_par *par, size_t offset, size_t len)
178 u16 *txbuf16 = par->txbuf.buf;
181 size_t tx_array_size;
185 fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s(offset=%zu, len=%zu)\n",
186 __func__, offset, len);
188 if (!par->txbuf.buf) {
189 dev_err(par->info->device, "%s: txbuf.buf is NULL\n", __func__);
194 vmem8 = par->info->screen_buffer + offset;
196 tx_array_size = par->txbuf.len / 2;
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);
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];
209 for (i = 0; i < to_copy; i++)
210 txbuf16[i] = 0x0100 | vmem8[i];
212 vmem8 = vmem8 + to_copy;
213 ret = par->fbtftops.write(par, par->txbuf.buf, to_copy * 2);
221 EXPORT_SYMBOL(fbtft_write_vmem16_bus9);
223 int fbtft_write_vmem8_bus8(struct fbtft_par *par, size_t offset, size_t len)
225 dev_err(par->info->device, "%s: function not implemented\n", __func__);
228 EXPORT_SYMBOL(fbtft_write_vmem8_bus8);
230 /* 16 bit pixel over 16-bit databus */
231 int fbtft_write_vmem16_bus16(struct fbtft_par *par, size_t offset, size_t len)
235 fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s(offset=%zu, len=%zu)\n",
236 __func__, offset, len);
238 vmem16 = (u16 *)(par->info->screen_buffer + offset);
240 /* no need for buffered write with 16-bit bus */
241 return fbtft_write_buf_dc(par, vmem16, len, 1);
243 EXPORT_SYMBOL(fbtft_write_vmem16_bus16);