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Commit 692fb0fe5aacea861e4006342029cf505a7dbe18

Authored by Qipan Li
Committed by Mark Brown
1 parent 6cca9e2dd0
Exists in smarc-imx_3.14.28_1.0.0_ga and in 1 other branch imx_3.14.28_1.0.0_ga

spi/sirf: fix the misunderstanding about len of spi_transfer 

the unit of len of spi_transfer is in bytes, not in spi words. the
old codes misunderstood that and thought the len is the amount of
spi words. but it is actually how many bytes existing in the spi
buffer.

this patch fixes that and also rename left_tx_cnt and left_rx_cnt
to left_tx_word and left_rx_word to highlight they are in words.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

Showing 1 changed file with 24 additions and 23 deletions Side-by-side Diff

drivers/spi/spi-sirf.c
Diff comments   View file @ 692fb0f
... ... @@ -130,8 +130,7 @@
130 130  
131 131 #define ALIGNED(x) (!((u32)x & 0x3))
132 132 #define IS_DMA_VALID(x) (x && ALIGNED(x->tx_buf) && ALIGNED(x->rx_buf) && \
133   - ALIGNED(x->len * sspi->word_width) && (x->len * sspi->word_width < \
134   - 2 * PAGE_SIZE))
  133 + ALIGNED(x->len) && (x->len < 2 * PAGE_SIZE))
135 134  
136 135 struct sirfsoc_spi {
137 136 struct spi_bitbang bitbang;
... ... @@ -152,8 +151,8 @@
152 151 void (*tx_word) (struct sirfsoc_spi *);
153 152  
154 153 /* number of words left to be tranmitted/received */
155   - unsigned int left_tx_cnt;
156   - unsigned int left_rx_cnt;
  154 + unsigned int left_tx_word;
  155 + unsigned int left_rx_word;
157 156  
158 157 /* rx & tx DMA channels */
159 158 struct dma_chan *rx_chan;
... ... @@ -178,7 +177,7 @@
178 177 sspi->rx = rx;
179 178 }
180 179  
181   - sspi->left_rx_cnt--;
  180 + sspi->left_rx_word--;
182 181 }
183 182  
184 183 static void spi_sirfsoc_tx_word_u8(struct sirfsoc_spi *sspi)
... ... @@ -192,7 +191,7 @@
192 191 }
193 192  
194 193 writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
195   - sspi->left_tx_cnt--;
  194 + sspi->left_tx_word--;
196 195 }
197 196  
198 197 static void spi_sirfsoc_rx_word_u16(struct sirfsoc_spi *sspi)
... ... @@ -207,7 +206,7 @@
207 206 sspi->rx = rx;
208 207 }
209 208  
210   - sspi->left_rx_cnt--;
  209 + sspi->left_rx_word--;
211 210 }
212 211  
213 212 static void spi_sirfsoc_tx_word_u16(struct sirfsoc_spi *sspi)
... ... @@ -221,7 +220,7 @@
221 220 }
222 221  
223 222 writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
224   - sspi->left_tx_cnt--;
  223 + sspi->left_tx_word--;
225 224 }
226 225  
227 226 static void spi_sirfsoc_rx_word_u32(struct sirfsoc_spi *sspi)
... ... @@ -236,7 +235,7 @@
236 235 sspi->rx = rx;
237 236 }
238 237  
239   - sspi->left_rx_cnt--;
  238 + sspi->left_rx_word--;
240 239  
241 240 }
242 241  
... ... @@ -251,7 +250,7 @@
251 250 }
252 251  
253 252 writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
254   - sspi->left_tx_cnt--;
  253 + sspi->left_tx_word--;
255 254 }
256 255  
257 256 static irqreturn_t spi_sirfsoc_irq(int irq, void *dev_id)
258 257  
259 258  
... ... @@ -272,18 +271,18 @@
272 271 | SIRFSOC_SPI_RXFIFO_THD_REACH))
273 272 while (!((readl(sspi->base + SIRFSOC_SPI_RXFIFO_STATUS)
274 273 & SIRFSOC_SPI_FIFO_EMPTY)) &&
275   - sspi->left_rx_cnt)
  274 + sspi->left_rx_word)
276 275 sspi->rx_word(sspi);
277 276  
278 277 if (spi_stat & (SIRFSOC_SPI_FIFO_EMPTY
279 278 | SIRFSOC_SPI_TXFIFO_THD_REACH))
280 279 while (!((readl(sspi->base + SIRFSOC_SPI_TXFIFO_STATUS)
281 280 & SIRFSOC_SPI_FIFO_FULL)) &&
282   - sspi->left_tx_cnt)
  281 + sspi->left_tx_word)
283 282 sspi->tx_word(sspi);
284 283  
285 284 /* Received all words */
286   - if ((sspi->left_rx_cnt == 0) && (sspi->left_tx_cnt == 0)) {
  285 + if ((sspi->left_rx_word == 0) && (sspi->left_tx_word == 0)) {
287 286 complete(&sspi->rx_done);
288 287 writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
289 288 }
290 289  
291 290  
292 291  
... ... @@ -305,25 +304,28 @@
305 304  
306 305 sspi->tx = t->tx_buf ? t->tx_buf : sspi->dummypage;
307 306 sspi->rx = t->rx_buf ? t->rx_buf : sspi->dummypage;
308   - sspi->left_tx_cnt = sspi->left_rx_cnt = t->len;
  307 + sspi->left_tx_word = sspi->left_rx_word = t->len / sspi->word_width;
309 308 INIT_COMPLETION(sspi->rx_done);
310 309 INIT_COMPLETION(sspi->tx_done);
311 310  
312 311 writel(SIRFSOC_SPI_INT_MASK_ALL, sspi->base + SIRFSOC_SPI_INT_STATUS);
313 312  
314   - if (t->len == 1) {
  313 + if (sspi->left_tx_word == 1) {
315 314 writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
316 315 SIRFSOC_SPI_ENA_AUTO_CLR,
317 316 sspi->base + SIRFSOC_SPI_CTRL);
318 317 writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
319 318 writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
320   - } else if ((t->len > 1) && (t->len < SIRFSOC_SPI_DAT_FRM_LEN_MAX)) {
  319 + } else if ((sspi->left_tx_word > 1) && (sspi->left_tx_word <
  320 + SIRFSOC_SPI_DAT_FRM_LEN_MAX)) {
321 321 writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
322 322 SIRFSOC_SPI_MUL_DAT_MODE |
323 323 SIRFSOC_SPI_ENA_AUTO_CLR,
324 324 sspi->base + SIRFSOC_SPI_CTRL);
325   - writel(t->len - 1, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
326   - writel(t->len - 1, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
  325 + writel(sspi->left_tx_word - 1,
  326 + sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
  327 + writel(sspi->left_tx_word - 1,
  328 + sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
327 329 } else {
328 330 writel(readl(sspi->base + SIRFSOC_SPI_CTRL),
329 331 sspi->base + SIRFSOC_SPI_CTRL);
330 332  
331 333  
... ... @@ -338,18 +340,17 @@
338 340  
339 341 if (IS_DMA_VALID(t)) {
340 342 struct dma_async_tx_descriptor *rx_desc, *tx_desc;
341   - unsigned int size = t->len * sspi->word_width;
342 343  
343 344 sspi->dst_start = dma_map_single(&spi->dev, sspi->rx, t->len, DMA_FROM_DEVICE);
344 345 rx_desc = dmaengine_prep_slave_single(sspi->rx_chan,
345   - sspi->dst_start, size, DMA_DEV_TO_MEM,
  346 + sspi->dst_start, t->len, DMA_DEV_TO_MEM,
346 347 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
347 348 rx_desc->callback = spi_sirfsoc_dma_fini_callback;
348 349 rx_desc->callback_param = &sspi->rx_done;
349 350  
350 351 sspi->src_start = dma_map_single(&spi->dev, (void *)sspi->tx, t->len, DMA_TO_DEVICE);
351 352 tx_desc = dmaengine_prep_slave_single(sspi->tx_chan,
352   - sspi->src_start, size, DMA_MEM_TO_DEV,
  353 + sspi->src_start, t->len, DMA_MEM_TO_DEV,
353 354 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
354 355 tx_desc->callback = spi_sirfsoc_dma_fini_callback;
355 356 tx_desc->callback_param = &sspi->tx_done;
... ... @@ -377,7 +378,7 @@
377 378 dev_err(&spi->dev, "transfer timeout\n");
378 379 dmaengine_terminate_all(sspi->rx_chan);
379 380 } else
380   - sspi->left_rx_cnt = 0;
  381 + sspi->left_rx_word = 0;
381 382  
382 383 /*
383 384 * we only wait tx-done event if transferring by DMA. for PIO,
... ... @@ -402,7 +403,7 @@
402 403 writel(0, sspi->base + SIRFSOC_SPI_TX_RX_EN);
403 404 writel(0, sspi->base + SIRFSOC_SPI_INT_EN);
404 405  
405   - return t->len - sspi->left_rx_cnt;
  406 + return t->len - sspi->left_rx_word * sspi->word_width;
406 407 }
407 408  
408 409 static void spi_sirfsoc_chipselect(struct spi_device *spi, int value)