spi/pl022: fix dubious allocation staticize platform data

This removes some dubious allocation of a local chipinfo struct
in favor of a constant preset, tagging that one const revealed
further problems with platform data being modified so fixed up
these too.

Reported-by: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 46 insertions, 50 deletions

diff --git a/drivers/spi/amba-pl022.c b/drivers/spi/amba-pl022.c
index 19d54aa31a36..fb3d1b31772d 100644
--- a/drivers/spi/amba-pl022.c
+++ b/drivers/spi/amba-pl022.c
@@ -1593,7 +1593,7 @@ static int destroy_queue(struct pl022 *pl022)
 }
 
 static int verify_controller_parameters(struct pl022 *pl022,
-                                        struct pl022_config_chip *chip_info)
+                                struct pl022_config_chip const *chip_info)
 {
         if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
             || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
@@ -1614,12 +1614,6 @@ static int verify_controller_parameters(struct pl022 *pl022,
                         "hierarchy is configured incorrectly\n");
                 return -EINVAL;
         }
-        if (((chip_info->clk_freq).cpsdvsr < CPSDVR_MIN)
-            || ((chip_info->clk_freq).cpsdvsr > CPSDVR_MAX)) {
-                dev_err(&pl022->adev->dev,
-                        "cpsdvsr is configured incorrectly\n");
-                return -EINVAL;
-        }
         if ((chip_info->com_mode != INTERRUPT_TRANSFER)
             && (chip_info->com_mode != DMA_TRANSFER)
             && (chip_info->com_mode != POLLING_TRANSFER)) {
@@ -1671,11 +1665,6 @@ static int verify_controller_parameters(struct pl022 *pl022,
                         return -EINVAL;
                 }
         }
-        if (chip_info->cs_control == NULL) {
-                dev_warn(&pl022->adev->dev,
-                        "Chip Select Function is NULL for this chip\n");
-                chip_info->cs_control = null_cs_control;
-        }
         return 0;
 }
 
@@ -1775,6 +1764,25 @@ static int calculate_effective_freq(struct pl022 *pl022,
         return 0;
 }
 
+
+/*
+ * A piece of default chip info unless the platform
+ * supplies it.
+ */
+static const struct pl022_config_chip pl022_default_chip_info = {
+        .com_mode = POLLING_TRANSFER,
+        .iface = SSP_INTERFACE_MOTOROLA_SPI,
+        .hierarchy = SSP_SLAVE,
+        .slave_tx_disable = DO_NOT_DRIVE_TX,
+        .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
+        .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
+        .ctrl_len = SSP_BITS_8,
+        .wait_state = SSP_MWIRE_WAIT_ZERO,
+        .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
+        .cs_control = null_cs_control,
+};
+
+
 /**
  * pl022_setup - setup function registered to SPI master framework
  * @spi: spi device which is requesting setup
@@ -1789,8 +1797,9 @@ static int calculate_effective_freq(struct pl022 *pl022,
  */
 static int pl022_setup(struct spi_device *spi)
 {
-        struct pl022_config_chip *chip_info;
+        struct pl022_config_chip const *chip_info;
         struct chip_data *chip;
+        struct ssp_clock_params clk_freq;
         int status = 0;
         struct pl022 *pl022 = spi_master_get_devdata(spi->master);
         unsigned int bits = spi->bits_per_word;
@@ -1817,40 +1826,13 @@ static int pl022_setup(struct spi_device *spi)
         chip_info = spi->controller_data;
 
         if (chip_info == NULL) {
+                chip_info = &pl022_default_chip_info;
                 /* spi_board_info.controller_data not is supplied */
                 dev_dbg(&spi->dev,
                         "using default controller_data settings\n");
-
-                chip_info =
-                        kzalloc(sizeof(struct pl022_config_chip), GFP_KERNEL);
-
-                if (!chip_info) {
-                        dev_err(&spi->dev,
-                                "cannot allocate controller data\n");
-                        status = -ENOMEM;
-                        goto err_first_setup;
-                }
-
-                dev_dbg(&spi->dev, "allocated memory for controller data\n");
-
-                /*
-                 * Set controller data default values:
-                 * Polling is supported by default
-                 */
-                chip_info->com_mode = POLLING_TRANSFER;
-                chip_info->iface = SSP_INTERFACE_MOTOROLA_SPI;
-                chip_info->hierarchy = SSP_SLAVE;
-                chip_info->slave_tx_disable = DO_NOT_DRIVE_TX;
-                chip_info->rx_lev_trig = SSP_RX_1_OR_MORE_ELEM;
-                chip_info->tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC;
-                chip_info->ctrl_len = SSP_BITS_8;
-                chip_info->wait_state = SSP_MWIRE_WAIT_ZERO;
-                chip_info->duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX;
-                chip_info->cs_control = null_cs_control;
-        } else {
+        } else
                 dev_dbg(&spi->dev,
                         "using user supplied controller_data settings\n");
-        }
 
         /*
          * We can override with custom divisors, else we use the board
@@ -1860,22 +1842,37 @@ static int pl022_setup(struct spi_device *spi)
             && (0 == chip_info->clk_freq.scr)) {
                 status = calculate_effective_freq(pl022,
                                                   spi->max_speed_hz,
-                                                  &chip_info->clk_freq);
+                                                  &clk_freq);
                 if (status < 0)
                         goto err_config_params;
         } else {
-                if ((chip_info->clk_freq.cpsdvsr % 2) != 0)
-                        chip_info->clk_freq.cpsdvsr =
-                                chip_info->clk_freq.cpsdvsr - 1;
+                memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
+                if ((clk_freq.cpsdvsr % 2) != 0)
+                        clk_freq.cpsdvsr =
+                                clk_freq.cpsdvsr - 1;
         }
+        if ((clk_freq.cpsdvsr < CPSDVR_MIN)
+            || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
+                dev_err(&spi->dev,
+                        "cpsdvsr is configured incorrectly\n");
+                goto err_config_params;
+        }
+
+
         status = verify_controller_parameters(pl022, chip_info);
         if (status) {
                 dev_err(&spi->dev, "controller data is incorrect");
                 goto err_config_params;
         }
+
         /* Now set controller state based on controller data */
         chip->xfer_type = chip_info->com_mode;
-        chip->cs_control = chip_info->cs_control;
+        if (!chip_info->cs_control) {
+                chip->cs_control = null_cs_control;
+                dev_warn(&spi->dev,
+                         "chip select function is NULL for this chip\n");
+        } else
+                chip->cs_control = chip_info->cs_control;
 
         if (bits <= 3) {
                 /* PL022 doesn't support less than 4-bits */
@@ -1932,7 +1929,7 @@ static int pl022_setup(struct spi_device *spi)
                                SSP_DMACR_MASK_TXDMAE, 1);
         }
 
-        chip->cpsr = chip_info->clk_freq.cpsdvsr;
+        chip->cpsr = clk_freq.cpsdvsr;
 
         /* Special setup for the ST micro extended control registers */
         if (pl022->vendor->extended_cr) {
@@ -1989,7 +1986,7 @@ static int pl022_setup(struct spi_device *spi)
                 tmp = SSP_CLK_FIRST_EDGE;
         SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
 
-        SSP_WRITE_BITS(chip->cr0, chip_info->clk_freq.scr, SSP_CR0_MASK_SCR, 8);
+        SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
         /* Loopback is available on all versions except PL023 */
         if (!pl022->vendor->pl023) {
                 if (spi->mode & SPI_LOOP)
@@ -2007,7 +2004,6 @@ static int pl022_setup(struct spi_device *spi)
         return status;
  err_config_params:
         spi_set_ctldata(spi, NULL);
- err_first_setup:
         kfree(chip);
         return status;
 }