Re: [PATCH 7/8] firmware: vpd: remove platform driver
On Wed, May 24, 2017 at 05:04:41PM -0700, Julius Werner wrote: > I'm not a kernel expert so maybe I don't understand this right, but... > I think this might have been done this way to ensure that the driver > can get initialized correctly regardless of probe ordering. > coreboot_table_find() may fail with -EPROBE_DEFER if the > coreboot_table driver and its dependent (coreboot_table-acpi or > coreboot_table-of) haven't been probed yet. In that case we want the > VPD driver to wait and try again later, after they've been probed. I > believe with the way this used to be written the driver core did that > automatically for us, but with your change I'm not sure if it still > does. Hmm, I missed that. OK, I think we have a maze of platform drivers there, I'll see what can be done. > > On Wed, May 24, 2017 at 10:22 AM, Guenter Roeck wrote: > > On Tue, May 23, 2017 at 5:07 PM, Dmitry Torokhov > > wrote: > >> There is no reason why VPD should register platform device and driver, > >> given that we do not use their respective kobjects to attach attributes, > >> nor do we need suspend/resume hooks, or any other features of device > >> core. > >> > >> Signed-off-by: Dmitry Torokhov > > > > One reason might be to use devm_ functions for memory allocations to > > simplify error handling and cleanup. Without that, I agree. > > > > Reviewed-by: Guenter Roeck > > > >> --- > >> drivers/firmware/google/vpd.c | 44 > >> --- > >> 1 file changed, 16 insertions(+), 28 deletions(-) > >> > >> diff --git a/drivers/firmware/google/vpd.c b/drivers/firmware/google/vpd.c > >> index 78945729388e..f4766bf6785a 100644 > >> --- a/drivers/firmware/google/vpd.c > >> +++ b/drivers/firmware/google/vpd.c > >> @@ -22,8 +22,6 @@ > >> #include > >> #include > >> #include > >> -#include > >> -#include > >> #include > >> #include > >> > >> @@ -279,47 +277,37 @@ static int vpd_sections_init(phys_addr_t physaddr) > >> ret = vpd_section_init("rw", &rw_vpd, > >>physaddr + sizeof(struct vpd_cbmem) > >> + > >>header.ro_size, header.rw_size); > >> - if (ret) > >> + if (ret) { > >> + vpd_section_destroy(&ro_vpd); > >> return ret; > >> + } > >> } > >> > >> return 0; > >> } > >> > >> -static int vpd_probe(struct platform_device *pdev) > >> -{ > >> - int ret; > >> - struct lb_cbmem_ref entry; > >> - > >> - ret = coreboot_table_find(CB_TAG_VPD, &entry, sizeof(entry)); > >> - if (ret) > >> - return ret; > >> - > >> - return vpd_sections_init(entry.cbmem_addr); > >> -} > >> - > >> -static struct platform_driver vpd_driver = { > >> - .probe = vpd_probe, > >> - .driver = { > >> - .name = "vpd", > >> - }, > >> -}; > >> - > >> static int __init vpd_platform_init(void) > >> { > >> - struct platform_device *pdev; > >> - > >> - pdev = platform_device_register_simple("vpd", -1, NULL, 0); > >> - if (IS_ERR(pdev)) > >> - return PTR_ERR(pdev); > >> + struct lb_cbmem_ref entry; > >> + int err; > >> > >> vpd_kobj = kobject_create_and_add("vpd", firmware_kobj); > >> if (!vpd_kobj) > >> return -ENOMEM; > >> > >> - platform_driver_register(&vpd_driver); > >> + err = coreboot_table_find(CB_TAG_VPD, &entry, sizeof(entry)); > >> + if (err) > >> + goto err_kobject_put; > >> + > >> + err = vpd_sections_init(entry.cbmem_addr); > >> + if (err) > >> + goto err_kobject_put; > >> > >> return 0; > >> + > >> +err_kobject_put: > >> + kobject_put(vpd_kobj); > >> + return err; > >> } > >> > >> static void __exit vpd_platform_exit(void) > >> -- > >> 2.13.0.219.gdb65acc882-goog > >> -- Dmitry
Re: [PATCH 7/8] firmware: vpd: remove platform driver
I'm not a kernel expert so maybe I don't understand this right, but... I think this might have been done this way to ensure that the driver can get initialized correctly regardless of probe ordering. coreboot_table_find() may fail with -EPROBE_DEFER if the coreboot_table driver and its dependent (coreboot_table-acpi or coreboot_table-of) haven't been probed yet. In that case we want the VPD driver to wait and try again later, after they've been probed. I believe with the way this used to be written the driver core did that automatically for us, but with your change I'm not sure if it still does. On Wed, May 24, 2017 at 10:22 AM, Guenter Roeck wrote: > On Tue, May 23, 2017 at 5:07 PM, Dmitry Torokhov > wrote: >> There is no reason why VPD should register platform device and driver, >> given that we do not use their respective kobjects to attach attributes, >> nor do we need suspend/resume hooks, or any other features of device >> core. >> >> Signed-off-by: Dmitry Torokhov > > One reason might be to use devm_ functions for memory allocations to > simplify error handling and cleanup. Without that, I agree. > > Reviewed-by: Guenter Roeck > >> --- >> drivers/firmware/google/vpd.c | 44 >> --- >> 1 file changed, 16 insertions(+), 28 deletions(-) >> >> diff --git a/drivers/firmware/google/vpd.c b/drivers/firmware/google/vpd.c >> index 78945729388e..f4766bf6785a 100644 >> --- a/drivers/firmware/google/vpd.c >> +++ b/drivers/firmware/google/vpd.c >> @@ -22,8 +22,6 @@ >> #include >> #include >> #include >> -#include >> -#include >> #include >> #include >> >> @@ -279,47 +277,37 @@ static int vpd_sections_init(phys_addr_t physaddr) >> ret = vpd_section_init("rw", &rw_vpd, >>physaddr + sizeof(struct vpd_cbmem) + >>header.ro_size, header.rw_size); >> - if (ret) >> + if (ret) { >> + vpd_section_destroy(&ro_vpd); >> return ret; >> + } >> } >> >> return 0; >> } >> >> -static int vpd_probe(struct platform_device *pdev) >> -{ >> - int ret; >> - struct lb_cbmem_ref entry; >> - >> - ret = coreboot_table_find(CB_TAG_VPD, &entry, sizeof(entry)); >> - if (ret) >> - return ret; >> - >> - return vpd_sections_init(entry.cbmem_addr); >> -} >> - >> -static struct platform_driver vpd_driver = { >> - .probe = vpd_probe, >> - .driver = { >> - .name = "vpd", >> - }, >> -}; >> - >> static int __init vpd_platform_init(void) >> { >> - struct platform_device *pdev; >> - >> - pdev = platform_device_register_simple("vpd", -1, NULL, 0); >> - if (IS_ERR(pdev)) >> - return PTR_ERR(pdev); >> + struct lb_cbmem_ref entry; >> + int err; >> >> vpd_kobj = kobject_create_and_add("vpd", firmware_kobj); >> if (!vpd_kobj) >> return -ENOMEM; >> >> - platform_driver_register(&vpd_driver); >> + err = coreboot_table_find(CB_TAG_VPD, &entry, sizeof(entry)); >> + if (err) >> + goto err_kobject_put; >> + >> + err = vpd_sections_init(entry.cbmem_addr); >> + if (err) >> + goto err_kobject_put; >> >> return 0; >> + >> +err_kobject_put: >> + kobject_put(vpd_kobj); >> + return err; >> } >> >> static void __exit vpd_platform_exit(void) >> -- >> 2.13.0.219.gdb65acc882-goog >> smime.p7s Description: S/MIME Cryptographic Signature
Re: [PATCH 7/8] firmware: vpd: remove platform driver
On Tue, May 23, 2017 at 5:07 PM, Dmitry Torokhov wrote: > There is no reason why VPD should register platform device and driver, > given that we do not use their respective kobjects to attach attributes, > nor do we need suspend/resume hooks, or any other features of device > core. > > Signed-off-by: Dmitry Torokhov One reason might be to use devm_ functions for memory allocations to simplify error handling and cleanup. Without that, I agree. Reviewed-by: Guenter Roeck > --- > drivers/firmware/google/vpd.c | 44 > --- > 1 file changed, 16 insertions(+), 28 deletions(-) > > diff --git a/drivers/firmware/google/vpd.c b/drivers/firmware/google/vpd.c > index 78945729388e..f4766bf6785a 100644 > --- a/drivers/firmware/google/vpd.c > +++ b/drivers/firmware/google/vpd.c > @@ -22,8 +22,6 @@ > #include > #include > #include > -#include > -#include > #include > #include > > @@ -279,47 +277,37 @@ static int vpd_sections_init(phys_addr_t physaddr) > ret = vpd_section_init("rw", &rw_vpd, >physaddr + sizeof(struct vpd_cbmem) + >header.ro_size, header.rw_size); > - if (ret) > + if (ret) { > + vpd_section_destroy(&ro_vpd); > return ret; > + } > } > > return 0; > } > > -static int vpd_probe(struct platform_device *pdev) > -{ > - int ret; > - struct lb_cbmem_ref entry; > - > - ret = coreboot_table_find(CB_TAG_VPD, &entry, sizeof(entry)); > - if (ret) > - return ret; > - > - return vpd_sections_init(entry.cbmem_addr); > -} > - > -static struct platform_driver vpd_driver = { > - .probe = vpd_probe, > - .driver = { > - .name = "vpd", > - }, > -}; > - > static int __init vpd_platform_init(void) > { > - struct platform_device *pdev; > - > - pdev = platform_device_register_simple("vpd", -1, NULL, 0); > - if (IS_ERR(pdev)) > - return PTR_ERR(pdev); > + struct lb_cbmem_ref entry; > + int err; > > vpd_kobj = kobject_create_and_add("vpd", firmware_kobj); > if (!vpd_kobj) > return -ENOMEM; > > - platform_driver_register(&vpd_driver); > + err = coreboot_table_find(CB_TAG_VPD, &entry, sizeof(entry)); > + if (err) > + goto err_kobject_put; > + > + err = vpd_sections_init(entry.cbmem_addr); > + if (err) > + goto err_kobject_put; > > return 0; > + > +err_kobject_put: > + kobject_put(vpd_kobj); > + return err; > } > > static void __exit vpd_platform_exit(void) > -- > 2.13.0.219.gdb65acc882-goog >
[PATCH 7/8] firmware: vpd: remove platform driver
There is no reason why VPD should register platform device and driver, given that we do not use their respective kobjects to attach attributes, nor do we need suspend/resume hooks, or any other features of device core. Signed-off-by: Dmitry Torokhov --- drivers/firmware/google/vpd.c | 44 --- 1 file changed, 16 insertions(+), 28 deletions(-) diff --git a/drivers/firmware/google/vpd.c b/drivers/firmware/google/vpd.c index 78945729388e..f4766bf6785a 100644 --- a/drivers/firmware/google/vpd.c +++ b/drivers/firmware/google/vpd.c @@ -22,8 +22,6 @@ #include #include #include -#include -#include #include #include @@ -279,47 +277,37 @@ static int vpd_sections_init(phys_addr_t physaddr) ret = vpd_section_init("rw", &rw_vpd, physaddr + sizeof(struct vpd_cbmem) + header.ro_size, header.rw_size); - if (ret) + if (ret) { + vpd_section_destroy(&ro_vpd); return ret; + } } return 0; } -static int vpd_probe(struct platform_device *pdev) -{ - int ret; - struct lb_cbmem_ref entry; - - ret = coreboot_table_find(CB_TAG_VPD, &entry, sizeof(entry)); - if (ret) - return ret; - - return vpd_sections_init(entry.cbmem_addr); -} - -static struct platform_driver vpd_driver = { - .probe = vpd_probe, - .driver = { - .name = "vpd", - }, -}; - static int __init vpd_platform_init(void) { - struct platform_device *pdev; - - pdev = platform_device_register_simple("vpd", -1, NULL, 0); - if (IS_ERR(pdev)) - return PTR_ERR(pdev); + struct lb_cbmem_ref entry; + int err; vpd_kobj = kobject_create_and_add("vpd", firmware_kobj); if (!vpd_kobj) return -ENOMEM; - platform_driver_register(&vpd_driver); + err = coreboot_table_find(CB_TAG_VPD, &entry, sizeof(entry)); + if (err) + goto err_kobject_put; + + err = vpd_sections_init(entry.cbmem_addr); + if (err) + goto err_kobject_put; return 0; + +err_kobject_put: + kobject_put(vpd_kobj); + return err; } static void __exit vpd_platform_exit(void) -- 2.13.0.219.gdb65acc882-goog