On 21-09-19, 20:27, Satendra Singh Thakur wrote: > On Wed, Sep 18, 2019 at 3:57 PM, Vinod Koul wrote: > > On 15-09-19, 12:30, Satendra Singh Thakur wrote: > > > 1. For most of the platform drivers's probe include following steps > > > > > > -memory allocation for driver's private structure > > > -getting io resources > > > -io remapping resources > > > -getting irq number > > > -registering irq > > > -setting driver's private data > > > -getting clock > > > -preparing and enabling clock > > > > And we have perfect set of APIs for these tasks! > Hi Vinod, > Thanks for the comments. > You are right, we already have set of APIs for these tasks. > The proposed macros combine the very same APIs to remove > duplicate/redundant code. > A new driver author can use these macros to easily write probe Nope they can write each APIs, know the exact flow and do it! > function without having to worry about signatures of internal APIs. > In the past, people have combined some of them e.g. > a) clk_prepare_enable combines clk_prepare and clk_enable As it is clock, it is called in sequence, whereas different drivers may have different sequencing. Btw I am not for adding maanged irq functions, they are really not the correct way to manage! > b) devm_platform_ioremap_resource combines > platform_get_resource (for type IORESOURCE_MEM) > and devm_ioremap_resource > c) module_platform_driver macro encompasses module_init/exit > and driver_register/unregister functions. All examples you are quoting do a set of functions (clk, resources etc and not do N things! > The basic idea is to simplyfy coding. > > > 2. We have defined a set of macros to combine some or all of > > > the above mentioned steps. This will remove redundant/duplicate > > > code in drivers' probe functions of platform drivers. > > > > Why, how does it help and you do realize it also introduces bugs > This will make probe function shorter by removing repeated code. > This will also reduce bugs caused due to improper handling > of failure cases because of these reasons: > a) If the developer calls each API individualy one might miss > proper handling of the failure for some API; Whereas the macro > properly handles failure of each API. > b) Macros are devres compatible which leaves less room for > memory leaks. No we review the code and if we miss we fix later! > Yes, the macros which enable clock and request irqs > might cause bugs if they are not used carefully. > For instance, enabling the clock or requesting the irq > earlier than actually required. So, the macros with _clk > and _irq, _all suffix should be used carefully. Precisely! > Please let me know if I miss any specific type of bug > here. > > > > > devm_platform_probe_helper(pdev, priv, clk_name); > > > devm_platform_probe_helper_clk(pdev, priv, clk_name); > > > devm_platform_probe_helper_irq(pdev, priv, clk_name, > > > irq_hndlr, irq_flags, irq_name, irq_devid); > > > devm_platform_probe_helper_all(pdev, priv, clk_name, > > > irq_hndlr, irq_flags, irq_name, irq_devid); > > > devm_platform_probe_helper_all_data(pdev, priv, clk_name, > > > irq_hndlr, irq_flags, irq_name, irq_devid); > > > > > > 3. Code is made devres compatible (wherever required) > > > The functions: clk_get, request_irq, kzalloc, platform_get_resource > > > are replaced with their devm_* counterparts. > > > > We already have devres APIs for people to use! > Yes, we have devres APIs and many drivers do use them. > But still there are many which don't use them. > The proposed macros provides just another way to use devres APIs. > > > > > > 4. Few bugs are also fixed. > > > > Which ones..? > The bug is that the failure of request_irq > is not handled properly in mtk-hsdma.c. This is fixed in patch [5/9]. > https://lkml.org/lkml/2019/9/15/35 Please send the fix individually and I would be glad to review. -- ~Vinod
