From 88ac039cbed125bd9ed132d27ec9f689c6442748 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 26 Feb 2020 12:18:38 +0200 Subject: dmaengine: Refactor dmaengine_check_align() to be bit operations only There is no need to have branch and temporary variable in the function. Simple convert it to be a set of bit and arithmetic operations. Signed-off-by: Andy Shevchenko Reviewed-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20200226101842.29426-1-andriy.shevchenko@linux.intel.com Signed-off-by: Vinod Koul --- include/linux/dmaengine.h | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) (limited to 'include/linux/dmaengine.h') diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 64461fc64e1b..9f3f5582816a 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -1155,14 +1155,7 @@ static inline dma_cookie_t dmaengine_submit(struct dma_async_tx_descriptor *desc static inline bool dmaengine_check_align(enum dmaengine_alignment align, size_t off1, size_t off2, size_t len) { - size_t mask; - - if (!align) - return true; - mask = (1 << align) - 1; - if (mask & (off1 | off2 | len)) - return false; - return true; + return !(((1 << align) - 1) & (off1 | off2 | len)); } static inline bool is_dma_copy_aligned(struct dma_device *dev, size_t off1, -- cgit v1.2.3 From 3a92063be16873a10648a81be0b1be42a9d54ee9 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 26 Feb 2020 12:18:39 +0200 Subject: dmaengine: Use negative condition for better readability When negative condition is in use we may decrease indentation level and make the main part of logic better visible. Signed-off-by: Andy Shevchenko Reviewed-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20200226101842.29426-2-andriy.shevchenko@linux.intel.com Signed-off-by: Vinod Koul --- include/linux/dmaengine.h | 35 ++++++++++++++++++----------------- 1 file changed, 18 insertions(+), 17 deletions(-) (limited to 'include/linux/dmaengine.h') diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 9f3f5582816a..ae56a91c2a05 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -618,10 +618,11 @@ static inline void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap) static inline void dma_descriptor_unmap(struct dma_async_tx_descriptor *tx) { - if (tx->unmap) { - dmaengine_unmap_put(tx->unmap); - tx->unmap = NULL; - } + if (!tx->unmap) + return; + + dmaengine_unmap_put(tx->unmap); + tx->unmap = NULL; } #ifndef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH @@ -1408,11 +1409,12 @@ static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie, static inline void dma_set_tx_state(struct dma_tx_state *st, dma_cookie_t last, dma_cookie_t used, u32 residue) { - if (st) { - st->last = last; - st->used = used; - st->residue = residue; - } + if (!st) + return; + + st->last = last; + st->used = used; + st->residue = residue; } #ifdef CONFIG_DMA_ENGINE @@ -1489,12 +1491,11 @@ static inline int dmaengine_desc_set_reuse(struct dma_async_tx_descriptor *tx) if (ret) return ret; - if (caps.descriptor_reuse) { - tx->flags |= DMA_CTRL_REUSE; - return 0; - } else { + if (!caps.descriptor_reuse) return -EPERM; - } + + tx->flags |= DMA_CTRL_REUSE; + return 0; } static inline void dmaengine_desc_clear_reuse(struct dma_async_tx_descriptor *tx) @@ -1510,10 +1511,10 @@ static inline bool dmaengine_desc_test_reuse(struct dma_async_tx_descriptor *tx) static inline int dmaengine_desc_free(struct dma_async_tx_descriptor *desc) { /* this is supported for reusable desc, so check that */ - if (dmaengine_desc_test_reuse(desc)) - return desc->desc_free(desc); - else + if (!dmaengine_desc_test_reuse(desc)) return -EPERM; + + return desc->desc_free(desc); } /* --- DMA device --- */ -- cgit v1.2.3 From 5f77dd850c0a32d4d5047d139077718ee7f1a8fe Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 26 Feb 2020 12:18:40 +0200 Subject: dmaengine: Drop redundant 'else' keyword It's obvious that 'else' keyword is redundant in the code like if (foo) return bar; else if (baz) ... Drop it for good. Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20200226101842.29426-3-andriy.shevchenko@linux.intel.com Signed-off-by: Vinod Koul --- include/linux/dmaengine.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/dmaengine.h') diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index ae56a91c2a05..1bb5477ef7ec 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -1230,9 +1230,9 @@ static inline int dma_maxpq(struct dma_device *dma, enum dma_ctrl_flags flags) { if (dma_dev_has_pq_continue(dma) || !dmaf_continue(flags)) return dma_dev_to_maxpq(dma); - else if (dmaf_p_disabled_continue(flags)) + if (dmaf_p_disabled_continue(flags)) return dma_dev_to_maxpq(dma) - 1; - else if (dmaf_continue(flags)) + if (dmaf_continue(flags)) return dma_dev_to_maxpq(dma) - 3; BUG(); } @@ -1243,7 +1243,7 @@ static inline size_t dmaengine_get_icg(bool inc, bool sgl, size_t icg, if (inc) { if (dir_icg) return dir_icg; - else if (sgl) + if (sgl) return icg; } -- cgit v1.2.3 From 1873300afa6147a1882aeba1e8bc9a13c5487571 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 26 Feb 2020 12:18:41 +0200 Subject: dmaengine: consistently return string literal from switch-case There is no need to have 'break;' statement in the default case followed by return certain string literal when all other cases have returned the string literals. So, refactor it accordingly. Signed-off-by: Andy Shevchenko Reviewed-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20200226101842.29426-4-andriy.shevchenko@linux.intel.com Signed-off-by: Vinod Koul --- include/linux/dmaengine.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'include/linux/dmaengine.h') diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 1bb5477ef7ec..d3672f065a64 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -1560,9 +1560,7 @@ dmaengine_get_direction_text(enum dma_transfer_direction dir) case DMA_DEV_TO_DEV: return "DEV_TO_DEV"; default: - break; + return "invalid"; } - - return "invalid"; } #endif /* DMAENGINE_H */ -- cgit v1.2.3 From e937cc1dd7966df33a478943817302502a164e25 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Fri, 6 Mar 2020 16:28:37 +0200 Subject: dmaengine: Add basic debugfs support Via the /sys/kernel/debug/dmaengine/summary users can get information about the DMA devices and the used channels. Example output on am654-evm with audio using two channels and after running dmatest on 4 channels: dma0 (285c0000.dma-controller): number of channels: 96 dma1 (31150000.dma-controller): number of channels: 267 dma1chan0 | 2b00000.mcasp:tx dma1chan1 | 2b00000.mcasp:rx dma1chan2 | in-use dma1chan3 | in-use dma1chan4 | in-use dma1chan5 | in-use For slave channels we can show the device and the channel name a given channel is requested. For non slave devices the only information we know is that the channel is in use. DMA drivers can implement the optional dbg_summary_show callback to provide controller specific information instead of the generic one. It is easy to extend the generic dmaengine_summary_show() to print additional information about the used channels. I have taken the idea from gpiolib and clk subsystems. Signed-off-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20200306142839.17910-2-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul --- include/linux/dmaengine.h | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'include/linux/dmaengine.h') diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index d3672f065a64..72920b5cf2d7 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -300,6 +300,8 @@ struct dma_router { * @chan_id: channel ID for sysfs * @dev: class device for sysfs * @name: backlink name for sysfs + * @dbg_client_name: slave name for debugfs in format: + * dev_name(requester's dev):channel name, for example: "2b00000.mcasp:tx" * @device_node: used to add this to the device chan list * @local: per-cpu pointer to a struct dma_chan_percpu * @client_count: how many clients are using this channel @@ -318,6 +320,9 @@ struct dma_chan { int chan_id; struct dma_chan_dev *dev; const char *name; +#ifdef CONFIG_DEBUG_FS + char *dbg_client_name; +#endif struct list_head device_node; struct dma_chan_percpu __percpu *local; @@ -806,7 +811,9 @@ struct dma_filter { * called and there are no further references to this structure. This * must be implemented to free resources however many existing drivers * do not and are therefore not safe to unbind while in use. - * + * @dbg_summary_show: optional routine to show contents in debugfs; default code + * will be used when this is omitted, but custom code can show extra, + * controller specific information. */ struct dma_device { struct kref ref; @@ -892,6 +899,10 @@ struct dma_device { struct dma_tx_state *txstate); void (*device_issue_pending)(struct dma_chan *chan); void (*device_release)(struct dma_device *dev); + /* debugfs support */ +#ifdef CONFIG_DEBUG_FS + void (*dbg_summary_show)(struct seq_file *s, struct dma_device *dev); +#endif }; static inline int dmaengine_slave_config(struct dma_chan *chan, -- cgit v1.2.3 From 26cf132de6f79c06025706ddc61e045d591d404d Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Fri, 6 Mar 2020 16:28:39 +0200 Subject: dmaengine: Create debug directories for DMA devices Create a placeholder directory for each registered DMA device. DMA drivers can use the dmaengine_get_debugfs_root() call to get their debugfs root and can populate with custom files to aim debugging. Signed-off-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20200306142839.17910-4-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul --- include/linux/dmaengine.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/dmaengine.h') diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 72920b5cf2d7..21065c04c4ac 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -902,6 +902,7 @@ struct dma_device { /* debugfs support */ #ifdef CONFIG_DEBUG_FS void (*dbg_summary_show)(struct seq_file *s, struct dma_device *dev); + struct dentry *dbg_dev_root; #endif }; -- cgit v1.2.3