mailbox: Convert from tasklet to BH workqueue

The only generic interface to execute asynchronously in the BH context is
tasklet; however, it's marked deprecated and has some design flaws. To
replace tasklets, BH workqueue support was recently added. A BH workqueue
behaves similarly to regular workqueues except that the queued work items
are executed in the BH context.

Based on the work done by Tejun Heo <tj@kernel.org>
Branch: https://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git for-6.10

Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>

diff --git a/drivers/mailbox/bcm-pdc-mailbox.c b/drivers/mailbox/bcm-pdc-mailbox.c
index 1768d3d5aaa011a1e2528bbc576aa3215d2bd2e1..242e7504a628c0f811f6243f5cf1215eca40d883 100644 (file)
--- a/drivers/mailbox/bcm-pdc-mailbox.c
+++ b/drivers/mailbox/bcm-pdc-mailbox.c
@@ -43,6 +43,7 @@
 #include <linux/dma-direction.h>
 #include <linux/dma-mapping.h>
 #include <linux/dmapool.h>
+#include <linux/workqueue.h>
 
 #define PDC_SUCCESS  0
 
@@ -293,8 +294,8 @@ struct pdc_state {
 
        unsigned int pdc_irq;
 
-       /* tasklet for deferred processing after DMA rx interrupt */
-       struct tasklet_struct rx_tasklet;
+       /* work for deferred processing after DMA rx interrupt */
+       struct work_struct rx_work;
 
        /* Number of bytes of receive status prior to each rx frame */
        u32 rx_status_len;
@@ -952,18 +953,18 @@ static irqreturn_t pdc_irq_handler(int irq, void *data)
        iowrite32(intstatus, pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET);
 
        /* Wakeup IRQ thread */
-       tasklet_schedule(&pdcs->rx_tasklet);
+       queue_work(system_bh_wq, &pdcs->rx_work);
        return IRQ_HANDLED;
 }
 
 /**
- * pdc_tasklet_cb() - Tasklet callback that runs the deferred processing after
+ * pdc_work_cb() - Work callback that runs the deferred processing after
  * a DMA receive interrupt. Reenables the receive interrupt.
  * @t: Pointer to the Altera sSGDMA channel structure
  */
-static void pdc_tasklet_cb(struct tasklet_struct *t)
+static void pdc_work_cb(struct work_struct *t)
 {
-       struct pdc_state *pdcs = from_tasklet(pdcs, t, rx_tasklet);
+       struct pdc_state *pdcs = from_work(pdcs, t, rx_work);
 
        pdc_receive(pdcs);
 
@@ -1577,8 +1578,8 @@ static int pdc_probe(struct platform_device *pdev)
 
        pdc_hw_init(pdcs);
 
-       /* Init tasklet for deferred DMA rx processing */
-       tasklet_setup(&pdcs->rx_tasklet, pdc_tasklet_cb);
+       /* Init work for deferred DMA rx processing */
+       INIT_WORK(&pdcs->rx_work, pdc_work_cb);
 
        err = pdc_interrupts_init(pdcs);
        if (err)
@@ -1595,7 +1596,7 @@ static int pdc_probe(struct platform_device *pdev)
        return PDC_SUCCESS;
 
 cleanup_buf_pool:
-       tasklet_kill(&pdcs->rx_tasklet);
+       cancel_work_sync(&pdcs->rx_work);
        dma_pool_destroy(pdcs->rx_buf_pool);
 
 cleanup_ring_pool:
@@ -1611,7 +1612,7 @@ static void pdc_remove(struct platform_device *pdev)
 
        pdc_free_debugfs();
 
-       tasklet_kill(&pdcs->rx_tasklet);
+       cancel_work_sync(&pdcs->rx_work);
 
        pdc_hw_disable(pdcs);
 

diff --git a/drivers/mailbox/imx-mailbox.c b/drivers/mailbox/imx-mailbox.c
index 5c1d09cad761265638f3d28b8cce46cf98e5061d..933727f89431db22ff1215ae6bf1c76331769c62 100644 (file)
--- a/drivers/mailbox/imx-mailbox.c
+++ b/drivers/mailbox/imx-mailbox.c
@@ -21,6 +21,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/suspend.h>
 #include <linux/slab.h>
+#include <linux/workqueue.h>
 
 #include "mailbox.h"
 
@@ -80,7 +81,7 @@ struct imx_mu_con_priv {
        char                    irq_desc[IMX_MU_CHAN_NAME_SIZE];
        enum imx_mu_chan_type   type;
        struct mbox_chan        *chan;
-       struct tasklet_struct   txdb_tasklet;
+       struct work_struct      txdb_work;
 };
 
 struct imx_mu_priv {
@@ -232,7 +233,7 @@ static int imx_mu_generic_tx(struct imx_mu_priv *priv,
                break;
        case IMX_MU_TYPE_TXDB:
                imx_mu_xcr_rmw(priv, IMX_MU_GCR, IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
-               tasklet_schedule(&cp->txdb_tasklet);
+               queue_work(system_bh_wq, &cp->txdb_work);
                break;
        case IMX_MU_TYPE_TXDB_V2:
                imx_mu_xcr_rmw(priv, IMX_MU_GCR, IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
@@ -420,7 +421,7 @@ static int imx_mu_seco_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp,
                }
 
                /* Simulate hack for mbox framework */
-               tasklet_schedule(&cp->txdb_tasklet);
+               queue_work(system_bh_wq, &cp->txdb_work);
 
                break;
        default:
@@ -484,9 +485,9 @@ exit:
        return err;
 }
 
-static void imx_mu_txdb_tasklet(unsigned long data)
+static void imx_mu_txdb_work(struct work_struct *t)
 {
-       struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data;
+       struct imx_mu_con_priv *cp = from_work(cp, t, txdb_work);
 
        mbox_chan_txdone(cp->chan, 0);
 }
@@ -570,8 +571,7 @@ static int imx_mu_startup(struct mbox_chan *chan)
 
        if (cp->type == IMX_MU_TYPE_TXDB) {
                /* Tx doorbell don't have ACK support */
-               tasklet_init(&cp->txdb_tasklet, imx_mu_txdb_tasklet,
-                            (unsigned long)cp);
+               INIT_WORK(&cp->txdb_work, imx_mu_txdb_work);
                return 0;
        }
 
@@ -615,7 +615,7 @@ static void imx_mu_shutdown(struct mbox_chan *chan)
        }
 
        if (cp->type == IMX_MU_TYPE_TXDB) {
-               tasklet_kill(&cp->txdb_tasklet);
+               cancel_work_sync(&cp->txdb_work);
                pm_runtime_put_sync(priv->dev);
                return;
        }