Hi Ivan,

On 03/25/2015 06:40 PM, Ivan T. Ivanov wrote:

Hi Sricharan,

On Fri, 2015-03-13 at 23:19 +0530, Sricharan R wrote:

quoted

  #define QUP_I2C_MASTER_GEN     0x408
+#define QUP_I2C_MASTER_CONFIG  0x408

Unused.

Ok, will remove it

quoted

  #define QUP_READ_LIMIT                 256
+#define MX_TX_RX_LEN                   SZ_64K
+#define MX_BLOCKS                      (MX_TX_RX_LEN / QUP_READ_LIMIT)
+
+#define TOUT_MAX                       300 /* Max timeout for 32k tx/tx */

seconds, muliseconds?

  Ok. Will add milliseconds.

quoted

  struct qup_i2c_config {
         int tag_ver;
         int max_freq;
  };

+struct tag {

Please use consistent naming convention.

ok.

quoted

+       u8 *start;
+       dma_addr_t addr;
+};
+
  struct qup_i2c_dev {
         struct device*dev;
         void __iomem*base;

@@ -157,9 +181,35 @@ struct qup_i2c_dev {
         /* QUP core errors */
         u32     qup_err;

+       /* dma parameters */
+       bool    is_dma;
+       struct  dma_pool *dpool;
+       struct  tag start_tag;
+       struct  tag scratch_tag;
+       struct  tag footer_tag;
+       struct  dma_chan *dma_tx;
+       struct  dma_chan *dma_rx;
+       struct  scatterlist *sg_tx;
+       struct  scatterlist *sg_rx;
+       dma_addr_tsg_tx_phys;
+       dma_addr_tsg_rx_phys;

Maybe these could be organized in structure per direction.

ok, will group it.

quoted

+
         struct completionxfer;
  };

+struct i2c_bam_xfer {

Unused.

  Right. Will remove the whole thing. Thanks.

quoted

+       struct qup_i2c_dev *qup;
+       u32 start_len;
+
+       u32 rx_nents;
+       u32 tx_nents;
+
+       struct dma_async_tx_descriptor *tx_desc;
+       dma_cookie_t tx_cookie;
+       struct dma_async_tx_descriptor *rx_desc;
+       dma_cookie_t rx_cookie;

structure per direction.

quoted

+};
+

  Infact should be removed.

quoted

+static void bam_i2c_callback(void *data)
+{

Please use consistent naming, here and bellow.

ok, will change.

quoted

+       struct qup_i2c_dev *qup = data;
+
+       complete(&qup->xfer);
+}
+
+static int get_start_tag(u8 *tag, struct i2c_msg *msg, int first, int last,
+                       int blen)
+{
+       u8 addr = (msg->addr << 1) | ((msg->flags & I2C_M_RD) == I2C_M_RD);
+       u8 op;
+       int len = 0;
+
+       /* always issue stop for each read block */
+       if (last) {
+               if (msg->flags & I2C_M_RD)
+                       op = QUP_TAG_V2_DATARD_STOP;
+               else
+                       op = QUP_TAG_V2_DATAWR_STOP;
+       } else {
+               if (msg->flags & I2C_M_RD)
+                       op = QUP_TAG_V2_DATARD;
+               else
+                       op = QUP_TAG_V2_DATAWR;
+       }
+
+       if (msg->flags & I2C_M_TEN) {
+               len += 5;
+               tag[0] = QUP_TAG_V2_START;
+               tag[1] = addr;
+               tag[2] = op;
+               tag[3] = blen;
+
+               if (msg->flags & I2C_M_RD && last) {
+                       len += 2;
+                       tag[4] = QUP_BAM_INPUT_EOT;
+                       tag[5] = QUP_BAM_FLUSH_STOP;
+               }
+       } else {
+               if (first) {
+                       tag[len++] = QUP_TAG_V2_START;
+                       tag[len++] = addr;
+               }
+
+               tag[len++] = op;
+               tag[len++] = blen;
+
+               if (msg->flags & I2C_M_RD & last) {
+                       tag[len++] = QUP_BAM_INPUT_EOT;
+                       tag[len++] = QUP_BAM_FLUSH_STOP;
+               }
+       }
+
+       return len;
+}

Maybe could be split to 2 functions?

hmm, ok will split couple of small ones.

quoted

-static const struct i2c_algorithm qup_i2c_algo = {
+static struct i2c_algorithm qup_i2c_algo = {

Why?

  oops. Should not have been changed. Will fix.

quoted

         .master_xfer= qup_i2c_xfer,
         .functionality= qup_i2c_func,
  };

@@ -839,6 +1136,7 @@ static int qup_i2c_probe(struct platform_device *pdev)
         u32 clk_freq = 100000;
         const struct qup_i2c_config *config;
         const struct of_device_id *of_id;
+       int blocks;

         qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL);
         if (!qup)

@@ -875,6 +1173,53 @@ static int qup_i2c_probe(struct platform_device *pdev)
                 return qup->irq;
         }

+       if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v2.1.1") ||
+               of_device_is_compatible(pdev->dev.of_node,
+                       "qcom,i2c-qup-v2.2.1")) {

Logic will be simpler if you check just for version 1 of the controller.

  yes. Will fix it.

quoted

+               qup->dma_rx = dma_request_slave_channel(&pdev->dev, "bam-rx");
+

Please use dma_request_slave_channel_reason.

As Andy noted, please use just "rx", "tx"

ok. will change it.

quoted

+               if (!qup->dma_rx)
+                       return -EPROBE_DEFER;

Don't mask other errors, here and bellow. DMA support should be optional.

  Ok, will fix here.

quoted

                 dev_err(qup->dev, "Could not get core clock\n");

@@ -989,6 +1334,14 @@ static int qup_i2c_remove(struct platform_device *pdev)
  {
         struct qup_i2c_dev *qup = platform_get_drvdata(pdev);

+       dma_pool_free(qup->dpool, qup->start_tag.start,
+                                                               qup->start_tag.addr);
+       dma_pool_free(qup->dpool, qup->scratch_tag.start,
+                                                               qup->scratch_tag.addr);
+       dma_pool_free(qup->dpool, qup->footer_tag.start,
+                                                               qup->footer_tag.addr);
+       dma_pool_destroy(qup->dpool);

Only if is_dma, right?

Right. Will add the check.

DMA mapping code omitted from review. I don't understand it well enough, sorry.

   Ok, thanks for reviewing the rest.

Regards,
  Sricharan

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