Re: [PATCH v5] ata/pata_buddha: Probe via modalias instead of initcall

Bartlomiej Zolnierkiewicz
2019-08-20T12:06:15Z

Hi Max,

Few more review comments below.

On 8/12/19 6:48 PM, Max Staudt wrote:
> Up until now, the pata_buddha driver would only check for cards on
> initcall time. Now, the kernel will call its probe function as soon
> as a compatible card is detected.
>
> v5: Remove module_exit(): There's no good way to handle the X-Surf hack.
> Also include a workaround to save X-Surf's drvdata in case zorro8390
> is active.
>
> v4: Clean up pata_buddha_probe() by using ent->driver_data.
> Support X-Surf via late_initcall()
>
> v3: Clean up devm_*, implement device removal.
>
> v2: Rename 'zdev' to 'z' to make the patch easy to analyse with
> git diff --ignore-space-change
>
> Signed-off-by: Max Staudt <max@enpas.org>
> ---
> drivers/ata/pata_buddha.c | 234 +++++++++++++++++++++++++++-------------------
> 1 file changed, 140 insertions(+), 94 deletions(-)
>
> diff --git a/drivers/ata/pata_buddha.c b/drivers/ata/pata_buddha.c
> index 11a8044ff..6014befc9 100644
> --- a/drivers/ata/pata_buddha.c
> +++ b/drivers/ata/pata_buddha.c
> @@ -18,7 +18,9 @@
> #include <linux/kernel.h>
> #include <linux/libata.h>
> #include <linux/mm.h>
> +#include <linux/mod_devicetable.h>
> #include <linux/module.h>
> +#include <linux/types.h>
> #include <linux/zorro.h>
> #include <scsi/scsi_cmnd.h>
> #include <scsi/scsi_host.h>
> @@ -29,7 +31,7 @@
> #include <asm/setup.h>
>
> #define DRV_NAME "pata_buddha"
> -#define DRV_VERSION "0.1.0"
> +#define DRV_VERSION "0.1.1"
>
> #define BUDDHA_BASE1 0x800
> #define BUDDHA_BASE2 0xa00
> @@ -47,11 +49,11 @@ enum {
> BOARD_XSURF
> };
>
> -static unsigned int buddha_bases[3] __initdata = {
> +static unsigned int buddha_bases[3] = {
> BUDDHA_BASE1, BUDDHA_BASE2, BUDDHA_BASE3
> };
>
> -static unsigned int xsurf_bases[2] __initdata = {
> +static unsigned int xsurf_bases[2] = {
> XSURF_BASE1, XSURF_BASE2
> };
>
> @@ -145,111 +147,155 @@ static struct ata_port_operations pata_xsurf_ops = {
> .set_mode = pata_buddha_set_mode,
> };
>
> -static int __init pata_buddha_init_one(void)
> +static int pata_buddha_probe(struct zorro_dev *z,
> + const struct zorro_device_id *ent)
> {
> - struct zorro_dev *z = NULL;
> -
> - while ((z = zorro_find_device(ZORRO_WILDCARD, z))) {
> - static const char *board_name[]
> - = { "Buddha", "Catweasel", "X-Surf" };
> - struct ata_host *host;
> - void __iomem *buddha_board;
> - unsigned long board;
> - unsigned int type, nr_ports = 2;
> - int i;
> -
> - if (z->id == ZORRO_PROD_INDIVIDUAL_COMPUTERS_BUDDHA) {
> - type = BOARD_BUDDHA;
> - } else if (z->id == ZORRO_PROD_INDIVIDUAL_COMPUTERS_CATWEASEL) {
> - type = BOARD_CATWEASEL;
> - nr_ports++;
> - } else if (z->id == ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF) {
> - type = BOARD_XSURF;
> - } else
> - continue;
> -
> - dev_info(&z->dev, "%s IDE controller\n", board_name[type]);
> -
> - board = z->resource.start;
> + static const char * const board_name[]
> + = { "Buddha", "Catweasel", "X-Surf" };
> + struct ata_host *host;
> + void __iomem *buddha_board;
> + unsigned long board;
> + unsigned int type = ent->driver_data;
> + unsigned int nr_ports = (type == BOARD_CATWEASEL) ? 3 : 2;
> + void *old_drvdata;
> + int i;
> +
> + dev_info(&z->dev, "%s IDE controller\n", board_name[type]);
> +
> + board = z->resource.start;
> +
> + if (type != BOARD_XSURF) {
> + if (!devm_request_mem_region(&z->dev,
> + board + BUDDHA_BASE1,
> + 0x800, DRV_NAME))
> + return -ENXIO;
> + } else {
> + if (!devm_request_mem_region(&z->dev,
> + board + XSURF_BASE1,
> + 0x1000, DRV_NAME))
> + return -ENXIO;
> + if (!devm_request_mem_region(&z->dev,
> + board + XSURF_BASE2,
> + 0x1000, DRV_NAME)) {
> + }
> + }
> +
> + /* Workaround for X-Surf: Save drvdata in case zorro8390 has set it */
> + old_drvdata = dev_get_drvdata(&z->dev);

This should be done only for type == BOARD_XSURF.

> + /* allocate host */
> + host = ata_host_alloc(&z->dev, nr_ports);
> + dev_set_drvdata(&z->dev, old_drvdata);

ditto

> + if (!host)
> + return -ENXIO;
> +
> +
> + buddha_board = ZTWO_VADDR(board);
> +
> + /* enable the board IRQ on Buddha/Catweasel */
> + if (type != BOARD_XSURF)
> + z_writeb(0, buddha_board + BUDDHA_IRQ_MR);
> +
> + for (i = 0; i < nr_ports; i++) {
> + struct ata_port *ap = host->ports[i];
> + void __iomem *base, *irqport;
> + unsigned long ctl = 0;
>
> if (type != BOARD_XSURF) {
> - if (!devm_request_mem_region(&z->dev,
> - board + BUDDHA_BASE1,
> - 0x800, DRV_NAME))
> - continue;
> + ap->ops = &pata_buddha_ops;
> + base = buddha_board + buddha_bases[i];
> + ctl = BUDDHA_CONTROL;
> + irqport = buddha_board + BUDDHA_IRQ + i * 0x40;
> } else {
> - if (!devm_request_mem_region(&z->dev,
> - board + XSURF_BASE1,
> - 0x1000, DRV_NAME))
> - continue;
> - if (!devm_request_mem_region(&z->dev,
> - board + XSURF_BASE2,
> - 0x1000, DRV_NAME))
> - continue;
> + ap->ops = &pata_xsurf_ops;
> + base = buddha_board + xsurf_bases[i];
> + /* X-Surf has no CS1* (Control/AltStat) */
> + irqport = buddha_board + XSURF_IRQ;
> }
>
> - /* allocate host */
> - host = ata_host_alloc(&z->dev, nr_ports);
> - if (!host)
> - continue;
> -
> - buddha_board = ZTWO_VADDR(board);
> -
> - /* enable the board IRQ on Buddha/Catweasel */
> - if (type != BOARD_XSURF)
> - z_writeb(0, buddha_board + BUDDHA_IRQ_MR);
> -
> - for (i = 0; i < nr_ports; i++) {
> - struct ata_port *ap = host->ports[i];
> - void __iomem *base, *irqport;
> - unsigned long ctl = 0;
> -
> - if (type != BOARD_XSURF) {
> - ap->ops = &pata_buddha_ops;
> - base = buddha_board + buddha_bases[i];
> - ctl = BUDDHA_CONTROL;
> - irqport = buddha_board + BUDDHA_IRQ + i * 0x40;
> - } else {
> - ap->ops = &pata_xsurf_ops;
> - base = buddha_board + xsurf_bases[i];
> - /* X-Surf has no CS1* (Control/AltStat) */
> - irqport = buddha_board + XSURF_IRQ;
> - }
> -
> - ap->pio_mask = ATA_PIO4;
> - ap->flags |= ATA_FLAG_SLAVE_POSS | ATA_FLAG_NO_IORDY;
> -
> - ap->ioaddr.data_addr = base;
> - ap->ioaddr.error_addr = base + 2 + 1 * 4;
> - ap->ioaddr.feature_addr = base + 2 + 1 * 4;
> - ap->ioaddr.nsect_addr = base + 2 + 2 * 4;
> - ap->ioaddr.lbal_addr = base + 2 + 3 * 4;
> - ap->ioaddr.lbam_addr = base + 2 + 4 * 4;
> - ap->ioaddr.lbah_addr = base + 2 + 5 * 4;
> - ap->ioaddr.device_addr = base + 2 + 6 * 4;
> - ap->ioaddr.status_addr = base + 2 + 7 * 4;
> - ap->ioaddr.command_addr = base + 2 + 7 * 4;
> -
> - if (ctl) {
> - ap->ioaddr.altstatus_addr = base + ctl;
> - ap->ioaddr.ctl_addr = base + ctl;
> - }
> -
> - ap->private_data = (void *)irqport;
> -
> - ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx", board,
> - ctl ? board + buddha_bases[i] + ctl : 0);
> + ap->pio_mask = ATA_PIO4;
> + ap->flags |= ATA_FLAG_SLAVE_POSS | ATA_FLAG_NO_IORDY;
> +
> + ap->ioaddr.data_addr = base;
> + ap->ioaddr.error_addr = base + 2 + 1 * 4;
> + ap->ioaddr.feature_addr = base + 2 + 1 * 4;
> + ap->ioaddr.nsect_addr = base + 2 + 2 * 4;
> + ap->ioaddr.lbal_addr = base + 2 + 3 * 4;
> + ap->ioaddr.lbam_addr = base + 2 + 4 * 4;
> + ap->ioaddr.lbah_addr = base + 2 + 5 * 4;
> + ap->ioaddr.device_addr = base + 2 + 6 * 4;
> + ap->ioaddr.status_addr = base + 2 + 7 * 4;
> + ap->ioaddr.command_addr = base + 2 + 7 * 4;
> +
> + if (ctl) {
> + ap->ioaddr.altstatus_addr = base + ctl;
> + ap->ioaddr.ctl_addr = base + ctl;
> }
>
> - ata_host_activate(host, IRQ_AMIGA_PORTS, ata_sff_interrupt,
> - IRQF_SHARED, &pata_buddha_sht);
> + ap->private_data = (void *)irqport;
>
> + ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx", board,
> + ctl ? board + buddha_bases[i] + ctl : 0);
> }
>
> + ata_host_activate(host, IRQ_AMIGA_PORTS, ata_sff_interrupt,
> + IRQF_SHARED, &pata_buddha_sht);
> +
> +
> return 0;
> }
>
> -module_init(pata_buddha_init_one);
> +static void pata_buddha_remove(struct zorro_dev *z)
> +{
> + struct ata_host *host = dev_get_drvdata(&z->dev);
> +
> + ata_host_detach(host);
> +}
> +
> +static const struct zorro_device_id pata_buddha_zorro_tbl[] = {
> + { ZORRO_PROD_INDIVIDUAL_COMPUTERS_BUDDHA, BOARD_BUDDHA},
> + { ZORRO_PROD_INDIVIDUAL_COMPUTERS_CATWEASEL, BOARD_CATWEASEL},
> + /* { ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF, BOARD_XSURF}, */

Commented out code should be removed.

> + { 0 }
> +};
> +

Extra newline, please remove it.

> +MODULE_DEVICE_TABLE(zorro, pata_buddha_zorro_tbl);
> +
> +static struct zorro_driver pata_buddha_driver = {
> + .name = "pata_buddha",
> + .id_table = pata_buddha_zorro_tbl,
> + .probe = pata_buddha_probe,
> + .remove = pata_buddha_remove,

I think that we should also add:

.driver = {
.suppress_bind_attrs = true,
},

to prevent the device from being unbinded (and thus ->remove called)
from the driver using sysfs interface.

> +};
> +

Extra newline, please remove it.

> +

ditto

> +
> +/*
> + * We cannot have a modalias for X-Surf boards, as it competes with the
> + * zorro8390 network driver. As a stopgap measure until we have proper
> + * MFC support for this board, we manually attach to it late after Zorro

s/MFC/MFD/

> + * has enumerated its boards.
> + */
> +static int __init pata_buddha_late_init(void)
> +{
> + struct zorro_dev *z = NULL;
> +
> + pr_info("pata_buddha: Scanning for stand-alone IDE controllers...\n");

I think that there is no need for being extra verbose,
please remove it.

> + zorro_register_driver(&pata_buddha_driver);
> +
> + pr_info("pata_buddha: Scanning for X-Surf boards...\n");

ditto

> + while ((z = zorro_find_device(ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF, z))) {
> + static struct zorro_device_id xsurf_ent =
> + { ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF, BOARD_XSURF};
> +
> + pata_buddha_probe(z, &xsurf_ent);
> + }
> +
> + return 0;
> +}
> +
> +late_initcall(pata_buddha_late_init);
> +

Extra newline, please remove it.

>
> MODULE_AUTHOR("Bartlomiej Zolnierkiewicz");
> MODULE_DESCRIPTION("low-level driver for Buddha/Catweasel/X-Surf PATA");

Please also always check your patches with scripts/checkpatch.pl and
fix the reported issues:

ERROR: code indent should use tabs where possible
#348: FILE: drivers/ata/pata_buddha.c:281:
+ struct zorro_dev *z = NULL;$

WARNING: please, no spaces at the start of a line
#348: FILE: drivers/ata/pata_buddha.c:281:
+ struct zorro_dev *z = NULL;$

WARNING: line over 80 characters
#354: FILE: drivers/ata/pata_buddha.c:287:
+ while ((z = zorro_find_device(ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF, z))) {

ERROR: code indent should use tabs where possible
#354: FILE: drivers/ata/pata_buddha.c:287:
+ while ((z = zorro_find_device(ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF, z))) {$

WARNING: please, no spaces at the start of a line
#354: FILE: drivers/ata/pata_buddha.c:287:
+ while ((z = zorro_find_device(ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF, z))) {$

ERROR: that open brace { should be on the previous line
#356: FILE: drivers/ata/pata_buddha.c:289:
+ static struct zorro_device_id xsurf_ent =
+ { ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF, BOARD_XSURF};

ERROR: code indent should use tabs where possible
#359: FILE: drivers/ata/pata_buddha.c:292:
+ }$

WARNING: please, no spaces at the start of a line
#359: FILE: drivers/ata/pata_buddha.c:292:
+ }$

ERROR: code indent should use tabs where possible
#361: FILE: drivers/ata/pata_buddha.c:294:
+ return 0;$

WARNING: please, no spaces at the start of a line
#361: FILE: drivers/ata/pata_buddha.c:294:
+ return 0;$

total: 5 errors, 6 warnings, 276 lines checked

Otherwise the patch looks fine.

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics