Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752022AbdIVDuH (ORCPT ); Thu, 21 Sep 2017 23:50:07 -0400 Received: from conuserg-09.nifty.com ([210.131.2.76]:59488 "EHLO conuserg-09.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751871AbdIVDsx (ORCPT ); Thu, 21 Sep 2017 23:48:53 -0400 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-09.nifty.com v8M3kwAR029389 X-Nifty-SrcIP: [153.142.97.92] From: Masahiro Yamada To: linux-mtd@lists.infradead.org Cc: Masahiro Yamada , Cyrille Pitchen , linux-kernel@vger.kernel.org, Boris Brezillon , Marek Vasut , Brian Norris , Richard Weinberger , David Woodhouse Subject: [PATCH v2 08/12] mtd: nand: denali: clean up comments Date: Fri, 22 Sep 2017 12:46:45 +0900 Message-Id: <1506052009-8285-9-git-send-email-yamada.masahiro@socionext.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1506052009-8285-1-git-send-email-yamada.masahiro@socionext.com> References: <1506052009-8285-1-git-send-email-yamada.masahiro@socionext.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7830 Lines: 236 This driver explains too much about what is apparent from the code. Comments around basic APIs such as init_completion(), spin_lock_init(), etc. seem unneeded lessons to kernel developers. (With those comments dropped, denali_drv_init() is small enough, so it has been merged into the probe function.) Also, NAND driver developers should know the NAND init procedure, so there is no need to explain nand_scan_ident/tail. I removed FSF's address from the license blocks, and added simple comments to struct members. Signed-off-by: Masahiro Yamada --- Changes in v2: - Add more comments to struct members drivers/mtd/nand/denali.c | 52 +++++-------------------------------------- drivers/mtd/nand/denali.h | 24 +++++++------------- drivers/mtd/nand/denali_dt.c | 1 - drivers/mtd/nand/denali_pci.c | 2 -- 4 files changed, 13 insertions(+), 66 deletions(-) diff --git a/drivers/mtd/nand/denali.c b/drivers/mtd/nand/denali.c index ca98015..02ce310 100644 --- a/drivers/mtd/nand/denali.c +++ b/drivers/mtd/nand/denali.c @@ -10,11 +10,6 @@ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. - * - * You should have received a copy of the GNU General Public License along with - * this program; if not, write to the Free Software Foundation, Inc., - * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. - * */ #include @@ -64,10 +59,6 @@ MODULE_LICENSE("GPL"); */ #define DENALI_CLK_X_MULT 6 -/* - * this macro allows us to convert from an MTD structure to our own - * device context (denali) structure. - */ static inline struct denali_nand_info *mtd_to_denali(struct mtd_info *mtd) { return container_of(mtd_to_nand(mtd), struct denali_nand_info, nand); @@ -450,9 +441,8 @@ static int denali_sw_ecc_fixup(struct mtd_info *mtd, } while (!(err_cor_info & ERR_CORRECTION_INFO__LAST_ERR)); /* - * Once handle all ecc errors, controller will trigger a - * ECC_TRANSACTION_DONE interrupt, so here just wait for - * a while for this interrupt + * Once handle all ECC errors, controller will trigger an + * ECC_TRANSACTION_DONE interrupt. */ irq_status = denali_wait_for_irq(denali, INTR__ECC_TRANSACTION_DONE); if (!(irq_status & INTR__ECC_TRANSACTION_DONE)) @@ -613,7 +603,6 @@ static int denali_dma_xfer(struct denali_nand_info *denali, void *buf, denali_reset_irq(denali); denali_setup_dma(denali, dma_addr, page, write); - /* wait for operation to complete */ irq_status = denali_wait_for_irq(denali, irq_mask); if (!(irq_status & INTR__DMA_CMD_COMP)) ret = -EIO; @@ -1185,22 +1174,6 @@ static const struct mtd_ooblayout_ops denali_ooblayout_ops = { .free = denali_ooblayout_free, }; -/* initialize driver data structures */ -static void denali_drv_init(struct denali_nand_info *denali) -{ - /* - * the completion object will be used to notify - * the callee that the interrupt is done - */ - init_completion(&denali->complete); - - /* - * the spinlock will be used to synchronize the ISR with any - * element that might be access shared data (interrupt status) - */ - spin_lock_init(&denali->irq_lock); -} - static int denali_multidev_fixup(struct denali_nand_info *denali) { struct nand_chip *chip = &denali->nand; @@ -1260,11 +1233,12 @@ int denali_init(struct denali_nand_info *denali) mtd->dev.parent = denali->dev; denali_hw_init(denali); - denali_drv_init(denali); + + init_completion(&denali->complete); + spin_lock_init(&denali->irq_lock); denali_clear_irq_all(denali); - /* Request IRQ after all the hardware initialization is finished */ ret = devm_request_irq(denali->dev, denali->irq, denali_isr, IRQF_SHARED, DENALI_NAND_NAME, denali); if (ret) { @@ -1282,7 +1256,6 @@ int denali_init(struct denali_nand_info *denali) if (!mtd->name) mtd->name = "denali-nand"; - /* register the driver with the NAND core subsystem */ chip->select_chip = denali_select_chip; chip->read_byte = denali_read_byte; chip->write_byte = denali_write_byte; @@ -1295,11 +1268,6 @@ int denali_init(struct denali_nand_info *denali) if (denali->clk_x_rate) chip->setup_data_interface = denali_setup_data_interface; - /* - * scan for NAND devices attached to the controller - * this is the first stage in a two step process to register - * with the nand subsystem - */ ret = nand_scan_ident(mtd, denali->max_banks, NULL); if (ret) goto disable_irq; @@ -1323,18 +1291,9 @@ int denali_init(struct denali_nand_info *denali) chip->buf_align = 16; } - /* - * second stage of the NAND scan - * this stage requires information regarding ECC and - * bad block management. - */ - chip->bbt_options |= NAND_BBT_USE_FLASH; chip->bbt_options |= NAND_BBT_NO_OOB; - chip->ecc.mode = NAND_ECC_HW_SYNDROME; - - /* no subpage writes on denali */ chip->options |= NAND_NO_SUBPAGE_WRITE; ret = denali_ecc_setup(mtd, chip, denali); @@ -1418,7 +1377,6 @@ int denali_init(struct denali_nand_info *denali) } EXPORT_SYMBOL(denali_init); -/* driver exit point */ void denali_remove(struct denali_nand_info *denali) { struct mtd_info *mtd = nand_to_mtd(&denali->nand); diff --git a/drivers/mtd/nand/denali.h b/drivers/mtd/nand/denali.h index 73aad3a..f55ee10 100644 --- a/drivers/mtd/nand/denali.h +++ b/drivers/mtd/nand/denali.h @@ -10,11 +10,6 @@ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. - * - * You should have received a copy of the GNU General Public License along with - * this program; if not, write to the Free Software Foundation, Inc., - * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. - * */ #ifndef __DENALI_H__ @@ -310,22 +305,19 @@ struct denali_nand_info { struct device *dev; void __iomem *reg; /* Register Interface */ void __iomem *host; /* Host Data/Command Interface */ - - /* elements used by ISR */ struct completion complete; - spinlock_t irq_lock; - uint32_t irq_mask; - uint32_t irq_status; + spinlock_t irq_lock; /* protect irq_mask and irq_status */ + u32 irq_mask; /* interrupts we are waiting for */ + u32 irq_status; /* interrupts that have happened */ int irq; - - void *buf; + void *buf; /* for syndrome layout conversion */ dma_addr_t dma_addr; - int dma_avail; + int dma_avail; /* can support DMA? */ int devs_per_cs; /* devices connected in parallel */ - int oob_skip_bytes; + int oob_skip_bytes; /* number of bytes reserved for BBM */ int max_banks; - unsigned int revision; - unsigned int caps; + unsigned int revision; /* IP revision */ + unsigned int caps; /* IP capability (or quirk) */ const struct nand_ecc_caps *ecc_caps; }; diff --git a/drivers/mtd/nand/denali_dt.c b/drivers/mtd/nand/denali_dt.c index 01e0100..cfd33e6 100644 --- a/drivers/mtd/nand/denali_dt.c +++ b/drivers/mtd/nand/denali_dt.c @@ -156,7 +156,6 @@ static struct platform_driver denali_dt_driver = { .of_match_table = denali_nand_dt_ids, }, }; - module_platform_driver(denali_dt_driver); MODULE_LICENSE("GPL"); diff --git a/drivers/mtd/nand/denali_pci.c b/drivers/mtd/nand/denali_pci.c index 7d5600b..57fb7ae 100644 --- a/drivers/mtd/nand/denali_pci.c +++ b/drivers/mtd/nand/denali_pci.c @@ -109,7 +109,6 @@ static int denali_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) return ret; } -/* driver exit point */ static void denali_pci_remove(struct pci_dev *dev) { struct denali_nand_info *denali = pci_get_drvdata(dev); @@ -125,5 +124,4 @@ static struct pci_driver denali_pci_driver = { .probe = denali_pci_probe, .remove = denali_pci_remove, }; - module_pci_driver(denali_pci_driver); -- 2.7.4