diff options
Diffstat (limited to 'drivers/spi/spi-pl022.c')
-rw-r--r-- | drivers/spi/spi-pl022.c | 58 |
1 files changed, 34 insertions, 24 deletions
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c index 09c925aaf32..400ae2121a2 100644 --- a/drivers/spi/spi-pl022.c +++ b/drivers/spi/spi-pl022.c @@ -1667,9 +1667,15 @@ static int calculate_effective_freq(struct pl022 *pl022, int freq, struct /* cpsdvsr = 254 & scr = 255 */ min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX); - if (!((freq <= max_tclk) && (freq >= min_tclk))) { + if (freq > max_tclk) + dev_warn(&pl022->adev->dev, + "Max speed that can be programmed is %d Hz, you requested %d\n", + max_tclk, freq); + + if (freq < min_tclk) { dev_err(&pl022->adev->dev, - "controller data is incorrect: out of range frequency"); + "Requested frequency: %d Hz is less than minimum possible %d Hz\n", + freq, min_tclk); return -EINVAL; } @@ -1681,26 +1687,37 @@ static int calculate_effective_freq(struct pl022 *pl022, int freq, struct while (scr <= SCR_MAX) { tmp = spi_rate(rate, cpsdvsr, scr); - if (tmp > freq) + if (tmp > freq) { + /* we need lower freq */ scr++; + continue; + } + /* - * If found exact value, update and break. - * If found more closer value, update and continue. + * If found exact value, mark found and break. + * If found more closer value, update and break. */ - else if ((tmp == freq) || (tmp > best_freq)) { + if (tmp > best_freq) { best_freq = tmp; best_cpsdvsr = cpsdvsr; best_scr = scr; if (tmp == freq) - break; + found = 1; } - scr++; + /* + * increased scr will give lower rates, which are not + * required + */ + break; } cpsdvsr += 2; scr = SCR_MIN; } + WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n", + freq); + clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF); clk_freq->scr = (u8) (best_scr & 0xFF); dev_dbg(&pl022->adev->dev, @@ -1823,9 +1840,12 @@ static int pl022_setup(struct spi_device *spi) } else chip->cs_control = chip_info->cs_control; - if (bits <= 3) { - /* PL022 doesn't support less than 4-bits */ + /* Check bits per word with vendor specific range */ + if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) { status = -ENOTSUPP; + dev_err(&spi->dev, "illegal data size for this controller!\n"); + dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n", + pl022->vendor->max_bpw); goto err_config_params; } else if (bits <= 8) { dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n"); @@ -1838,20 +1858,10 @@ static int pl022_setup(struct spi_device *spi) chip->read = READING_U16; chip->write = WRITING_U16; } else { - if (pl022->vendor->max_bpw >= 32) { - dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n"); - chip->n_bytes = 4; - chip->read = READING_U32; - chip->write = WRITING_U32; - } else { - dev_err(&spi->dev, - "illegal data size for this controller!\n"); - dev_err(&spi->dev, - "a standard pl022 can only handle " - "1 <= n <= 16 bit words\n"); - status = -ENOTSUPP; - goto err_config_params; - } + dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n"); + chip->n_bytes = 4; + chip->read = READING_U32; + chip->write = WRITING_U32; } /* Now Initialize all register settings required for this chip */ |