From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754052AbcKBHpA (ORCPT ); Wed, 2 Nov 2016 03:45:00 -0400 Received: from kvm5.telegraphics.com.au ([98.124.60.144]:46032 "EHLO kvm5.telegraphics.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753831AbcKBHo7 (ORCPT ); Wed, 2 Nov 2016 03:44:59 -0400 Date: Wed, 2 Nov 2016 18:45:04 +1100 (AEDT) From: Finn Thain To: Ondrej Zary cc: Christoph Hellwig , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/6] NCR5380: Use probe_irq_*() for IRQ probing In-Reply-To: <1477945112-25659-2-git-send-email-linux@rainbow-software.org> Message-ID: References: <1477945112-25659-1-git-send-email-linux@rainbow-software.org> <1477945112-25659-2-git-send-email-linux@rainbow-software.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 31 Oct 2016, Ondrej Zary wrote: > Use standard probe_irq_on() and probe_irq_off() functions instead of own > implementation. This prevents warning messages like this in the kernel > log: genirq: Flags mismatch irq 1. 00000000 (NCR-probe) vs. 00000080 > (i8042) > > Move the IRQ trigger code to a separate function so it can be used for > other purposes (testing if the IRQ works) and move the code from NCR5380 > to g_NCR5380. > > Also add missing IRQ reset before and after the probe. > > Signed-off-by: Ondrej Zary > --- > drivers/scsi/NCR5380.c | 77 +--------------------------------------------- > drivers/scsi/NCR5380.h | 1 - > drivers/scsi/g_NCR5380.c | 50 +++++++++++++++++++++++++++++- > 3 files changed, 50 insertions(+), 78 deletions(-) > > diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c > index d849ffa..4f5ca79 100644 > --- a/drivers/scsi/NCR5380.c > +++ b/drivers/scsi/NCR5380.c > @@ -97,9 +97,6 @@ > * and macros and include this file in your driver. > * > * These macros control options : > - * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be > - * defined. > - * > * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically > * for commands that return with a CHECK CONDITION status. > * > @@ -127,9 +124,7 @@ > * NCR5380_dma_residual - residual byte count > * > * The generic driver is initialized by calling NCR5380_init(instance), > - * after setting the appropriate host specific fields and ID. If the > - * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance, > - * possible) function may be used. > + * after setting the appropriate host specific fields and ID. > */ > > #ifndef NCR5380_io_delay > @@ -351,76 +346,6 @@ static void NCR5380_print_phase(struct Scsi_Host *instance) > } > #endif > > - > -static int probe_irq; > - > -/** > - * probe_intr - helper for IRQ autoprobe > - * @irq: interrupt number > - * @dev_id: unused > - * @regs: unused > - * > - * Set a flag to indicate the IRQ in question was received. This is > - * used by the IRQ probe code. > - */ > - > -static irqreturn_t probe_intr(int irq, void *dev_id) > -{ > - probe_irq = irq; > - return IRQ_HANDLED; > -} > - > -/** > - * NCR5380_probe_irq - find the IRQ of an NCR5380 > - * @instance: NCR5380 controller > - * @possible: bitmask of ISA IRQ lines > - * > - * Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ > - * and then looking to see what interrupt actually turned up. > - */ > - > -static int __maybe_unused NCR5380_probe_irq(struct Scsi_Host *instance, > - int possible) > -{ > - struct NCR5380_hostdata *hostdata = shost_priv(instance); > - unsigned long timeout; > - int trying_irqs, i, mask; > - > - for (trying_irqs = 0, i = 1, mask = 2; i < 16; ++i, mask <<= 1) > - if ((mask & possible) && (request_irq(i, &probe_intr, 0, "NCR-probe", NULL) == 0)) > - trying_irqs |= mask; > - > - timeout = jiffies + msecs_to_jiffies(250); > - probe_irq = NO_IRQ; > - > - /* > - * A interrupt is triggered whenever BSY = false, SEL = true > - * and a bit set in the SELECT_ENABLE_REG is asserted on the > - * SCSI bus. > - * > - * Note that the bus is only driven when the phase control signals > - * (I/O, C/D, and MSG) match those in the TCR, so we must reset that > - * to zero. > - */ > - > - NCR5380_write(TARGET_COMMAND_REG, 0); > - NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); > - NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); > - NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL); > - > - while (probe_irq == NO_IRQ && time_before(jiffies, timeout)) > - schedule_timeout_uninterruptible(1); > - > - NCR5380_write(SELECT_ENABLE_REG, 0); > - NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); > - > - for (i = 1, mask = 2; i < 16; ++i, mask <<= 1) > - if (trying_irqs & mask) > - free_irq(i, NULL); > - > - return probe_irq; > -} > - > /** > * NCR58380_info - report driver and host information > * @instance: relevant scsi host instance > diff --git a/drivers/scsi/NCR5380.h b/drivers/scsi/NCR5380.h > index 3c6ce54..4724558 100644 > --- a/drivers/scsi/NCR5380.h > +++ b/drivers/scsi/NCR5380.h > @@ -290,7 +290,6 @@ static inline struct scsi_cmnd *NCR5380_to_scmd(struct NCR5380_cmd *ncmd_ptr) > #define NCR5380_dprint_phase(flg, arg) do {} while (0) > #endif > > -static int NCR5380_probe_irq(struct Scsi_Host *instance, int possible); > static int NCR5380_init(struct Scsi_Host *instance, int flags); > static int NCR5380_maybe_reset_bus(struct Scsi_Host *); > static void NCR5380_exit(struct Scsi_Host *instance); > diff --git a/drivers/scsi/g_NCR5380.c b/drivers/scsi/g_NCR5380.c > index 7299ad9..09c660b 100644 > --- a/drivers/scsi/g_NCR5380.c > +++ b/drivers/scsi/g_NCR5380.c > @@ -67,6 +67,54 @@ > MODULE_ALIAS("g_NCR5380_mmio"); > MODULE_LICENSE("GPL"); > > +static void NCR5380_trigger_irq(struct Scsi_Host *instance) That should be 'g_NCR5380_trigger_irq' (if it needs a prefix). > +{ > + struct NCR5380_hostdata *hostdata = shost_priv(instance); > + > + /* > + * An interrupt is triggered whenever BSY = false, SEL = true > + * and a bit set in the SELECT_ENABLE_REG is asserted on the > + * SCSI bus. > + * > + * Note that the bus is only driven when the phase control signals > + * (I/O, C/D, and MSG) match those in the TCR, so we must reset that > + * to zero. > + */ > + NCR5380_write(TARGET_COMMAND_REG, 0); That assumes bus free phase, which we hope is the case but NCR5380_maybe_reset_bus() doesn't guarantee it. This is more robust: * Note that the bus is only driven when the phase control signals * (I/O, C/D, and MSG) match those in the TCR. */ NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK)); > + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); > + NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); > + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL); > + > + usleep_range(1000, 20000); Again, msleep(1) would be more appropriate here. > + > + NCR5380_write(SELECT_ENABLE_REG, 0); > + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); > +} > + > +/** > + * NCR5380_probe_irq - find the IRQ of an NCR5380 This should be 'g_NCR5380_probe_irq' (if it needs a prefix). > + * @instance: NCR5380 controller > + * > + * Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ > + * and then looking to see what interrupt actually turned up. > + */ > + > +static int NCR5380_probe_irq(struct Scsi_Host *instance) > +{ > + struct NCR5380_hostdata *hostdata = shost_priv(instance); > + int irq_mask, irq; > + > + NCR5380_read(RESET_PARITY_INTERRUPT_REG); > + irq_mask = probe_irq_on(); > + NCR5380_trigger_irq(instance); > + irq = probe_irq_off(irq_mask); > + NCR5380_read(RESET_PARITY_INTERRUPT_REG); > + if (irq < 0) > + irq = NO_IRQ; > + > + return irq; > +} > + > /* > * Configure I/O address of 53C400A or DTC436 by writing magic numbers > * to ports 0x779 and 0x379. > @@ -265,7 +313,7 @@ static int generic_NCR5380_init_one(struct scsi_host_template *tpnt, > if (irq != IRQ_AUTO) > instance->irq = irq; > else > - instance->irq = NCR5380_probe_irq(instance, 0xffff); > + instance->irq = NCR5380_probe_irq(instance); > > /* Compatibility with documented NCR5380 kernel parameters */ > if (instance->irq == 255) > --